Add safe.directory for git config

otherwise colcon cache errors out because of issues with git
due to complex user mapping magic that vscode does with devcontainers

https://stackoverflow.com/questions/72978485/git-submodule-update-failed-with-fatal-detected-dubious-ownership-in-repositor

also used by Moveit2:
moveit/moveit2#1994

https://github.blog/2022-04-12-git-security-vulnerability-announced/

Author: ruffsl

.devcontainer/on-create-command.sh

@@ -9,6 +9,7 @@ env
 cd $OVERLAY_WS
 . $UNDERLAY_WS/install/setup.sh
 
+git config --global --add safe.directory "*"
 colcon cache lock
 
 colcon build \