Remove centering for floats (#364)

This was a bad idea...:
https://tex.stackexchange.com/questions/2651/should-i-use-center-or-centering-for-figures-and-tables

floatrows not sure how it should work with flowcharts... so we use
centring

I don't want to redefine all floats either as we use them for chapters
title page.

book/wheat-sourdough/wheat-sourdough.tex

@@ -45,11 +45,10 @@ that tastes much better than any store-bought bread.
 \section{The process}
 
 \begin{flowchart}[!htb]
-\begin{center}
+\centering
   \input{figures/fig-wheat-sourdough-process.tex}
   \caption{The typical process of making a wheat-based sourdough bread.}%
   \label{fig:wheat-sourdough-process}
-\end{center}
 \end{flowchart}
 
 The whole process of making great sourdough bread starts with
@@ -99,7 +98,7 @@ doesn't have a good balance of yeast to bacteria, so will your
 main dough.
 
 \begin{flowchart}[!htb]
-\begin{center}
+\centering
   \input{figures/fig-starter-readiness.tex}
   \caption[Process to prepare your starter before baking]{The process to check
       your sourdough starter when making wheat-based doughs. In practice
@@ -110,7 +109,6 @@ main dough.
       shown water quantities, i.e., if the chart shows \qty{100}{\gram} of
       water, use \qtyrange{50}{60}{\gram} of water for your stiff starter.}%
   \label{fig:process-starter-wheat-sourdough}
-\end{center}
 \end{flowchart}
 
 Generally, think of the dough you are mixing as a big starter with salt.
@@ -520,12 +518,11 @@ value to \qtyrange{5}{10}{\percent}. The other option could be to place the doug
 environment and thus reduce the speed at which your microorganisms replicate.
 
 \begin{table}[!htb]
-    \begin{center}
+    \centering
         \input{tables/table-starter-usage-activity.tex}
         \caption[Quantity of sourdough]{A table visualizing how much sourdough
             starter to use depending on temperature and the starter's activity
             level.}
-    \end{center}
 \end{table}
 
 Based on my experience and my sourdough, my ideal bread always takes around 8
@@ -561,11 +558,10 @@ all the gases during the fermentation process. Without the gluten network,
 the gases would just diffuse out of your dough.
 
 \begin{flowchart}[!htb]
-\begin{center}
+\centering
   \input{figures/fig-kneading-process.tex}
   \caption{The gluten development process for a wheat-based dough.}%
   \label{fig:wheat-sourdough-kneading-process}
-\end{center}
 \end{flowchart}
 
 It might sound odd, but the most important part of kneading is waiting. By
@@ -751,12 +747,11 @@ flavor of the resulting bread is better compared to a pale
 underfermented dough.
 
 \begin{table}[!htb]
-    \begin{center}
+    \centering
         \input{tables/table-fermentation-effects.tex}
         \caption[Stages of sourdough fermentation]{The different stages of
             sourdough fermentation and the effects on crumb, alveoli, texture,
             and overall taste.}
-    \end{center}
 \end{table}
 
 The worst thing you can do when fermenting sourdough
@@ -777,7 +772,7 @@ is much larger. The doughs are perfect to be made in a
 machine.
 
 \begin{flowchart}[!htb]
-\begin{center}
+\centering
   \input{figures/fig-bulk-fermentation.tex}
   \caption[Process to check the bulk fermentation]{During the bulk
       fermentation, multiple doughs are fermented together in bulk.  A
@@ -785,7 +780,6 @@ machine.
       stage of fermentation is completed. This chart shows multiple available
       options to check on the bulk fermentation progress.}%
   \label{fig:bulk-fermentation}
-\end{center}
 \end{flowchart}
 
 Experienced bakers will tell you to go by the look and feel of
@@ -814,12 +808,11 @@ up to \qty{100}{\percent} with subsequent bakes. Then identify a value
 that you are happy with.
 
 \begin{table}[!htb]
-    \begin{center}
+    \centering
         \input{tables/table-dough-size-increase.tex}
         \caption[Increase of size versus protein content]{Reference values for
             how much size increase to aim for with an aliquot jar depending on
             the dough's protein content.}
-    \end{center}
 \end{table}
 
 The beauty of the aliquot is that no matter the surrounding
@@ -896,12 +889,11 @@ bread didn't turn out the way you like, either shorten
 the fermentation or extend it a little bit.
 
 \begin{table}[!htb]
-    \begin{center}
+    \centering
         \input{tables/table-ph-values-dough.tex}%
         \caption[Dough's pH during bread preparation]{Example pH values for
             the different breakpoints of my own sourdough process.}%
         \label{table:sample-ph-values}
-    \end{center}
 \end{table}
 
 The beauty of this method is its reliability. Once you have found
@@ -1120,12 +1112,11 @@ The step is required if you are making multiple loaves in one
 batch. It is optional if you are making a single loaf.
 
 \begin{flowchart}[!htb]
-\begin{center}
+\centering
   \input{figures/fig-dividing-preshaping.tex}
   \caption[Is dividing your dough required check]{Dividing is only required when you are
       making multiple loaves in a single dough batch.}%
   \label{fig:dividing-decision-tree}
-\end{center}
 \end{flowchart}
 
 The goal of dividing your dough into smaller pieces is to portion
@@ -1235,12 +1226,11 @@ your environment.
 \section{Shaping}
 
 \begin{flowchart}[!htb]
-\begin{center}
+\centering
   \input{figures/fig-shaping-process.tex}
   \caption[Sourdough shaping process]{A schematic visualization of the shaping process
       including checks for an overfermented dough.}%
   \label{fig:shaping-decision-tree}
-\end{center}
 \end{flowchart}
 
 Shaping will give your dough the final shape before baking. After
@@ -1460,13 +1450,12 @@ their biochemical processes. More research is needed on the topic
 of retarding and flavor development.
 
 \begin{flowchart}[!htb]
-\begin{center}
+\centering
   \input{figures/fig-proofing-process.tex}
   \caption[Sourdough proofing process]{A schematic overview of the different steps of
       the sourdough proofing process. The proofing technique to choose depends
       on your availability and schedule.}%
   \label{fig:proofing-process}
-\end{center}
 \end{flowchart}
 
 To me, the sole purpose of cold-proofing is its ability to allow you