MSYS2: Use date of last git commit instead of current date for packed filename

build_scripts/Windows-msys2/tools/get-rs-date.bat

@@ -0,0 +1,32 @@
+REM Usage:
+REM call get-rs-date.bat SourcePath Variable
+
+setlocal
+
+set SourcePath=%~1
+set Variable=%~2
+if "%Variable%"=="" (
+	echo.
+	echo Parameter error
+	exit /B 1
+)
+
+:: Check git executable
+set GitPath=
+call "%~dp0find-in-path.bat" GitPath git.exe
+if "%GitPath%"=="" (
+	echo.
+	echo Git executable not found in PATH.
+	exit /B 1
+)
+
+set Date=
+
+pushd "%SourcePath%"
+rem This doesn't work: git log -1 --date=format:"%Y%m%d" --format="%ad"
+for /F "tokens=1,2,3* delims=-" %%A in ('git log -1 --date^=short --format^="%%ad"') do set Date=%%A%%B%%C
+popd
+
+:exit
+endlocal & set %Variable%=%Date%
+exit /B 0