Ports: Make package.sh dev work with ports that have slashes in $workdir

Author: https://github.com/alimpfard
Commit: dcf8385e5b
Pull-request: https://github.com/SerenityOS/serenity/pull/14055
Reviewed-by: https://github.com/danners
Reviewed-by: https://github.com/timschumi

Ports/.port_include.sh

@@ -711,7 +711,7 @@ do_dev() {
         exit 1
     fi
 
-    git_repo=".$workdir-git"
+    git_repo=".${workdir////_}-git"
     [ -d "$git_repo" ] || (
         mv "$workdir" "$git_repo"
         pushd "$git_repo"