20230913 setup GIT_PYTHON_GIT_EXECUTABLE for GitPython

webui.bat

@@ -1,6 +1,7 @@
 @echo off
 
 if not defined PYTHON (set PYTHON=python)
+if defined GIT (set "GIT_PYTHON_GIT_EXECUTABLE=%GIT%")
 if not defined VENV_DIR (set "VENV_DIR=%~dp0%venv")
 
 set SD_WEBUI_RESTART=tmp/restart

webui.sh

@@ -51,6 +51,8 @@ fi
 if [[ -z "${GIT}" ]]
 then
     export GIT="git"
+else
+    export GIT_PYTHON_GIT_EXECUTABLE="${GIT}"
 fi
 
 # python3 venv without trailing slash (defaults to ${install_dir}/${clone_dir}/venv)