Upped Python version used on windows, and documented that workflow.ym…

…l needs to be checked.

.github/workflows/build.yml

@@ -21,7 +21,7 @@ jobs:
         - name: Install correct Python version
           uses: actions/setup-python@v5
           with:
-            python-version: '3.11'
+            python-version: '3.12'
         - name: Pre-install (Windows)
           shell: pwsh
           run: |

readme.md

@@ -389,6 +389,7 @@ When creating a new release, ensure the following have been done
 	- Update `scripts/install-3rdparty-full-win1034.ps1` with the best Python version.
 	- Update `scripts/install-3rdparty-osx1015.sh` with the best Python version.
 	- Check the Ubuntu install-3rdparty scripts for which Python they install.
+	- Check `.github/workflows/build.yml` for the Python versions used.
 
 - Dependencies for the `.deb` installer for apt/Ubuntu need to be updated. There may be better ways to do this, but this works:
   - On the targeted Ubuntu, check out and edit `CMakeFiles/CwipcInstallers.cmake`