get_snapshot: Add UPSTREAM_GIT_NOREPO to forbid any repo interaction

get_snapshot

@@ -31,6 +31,7 @@ workdir=`pwd`
 
 set -x
 
+if [ -z "$UPSTREAM_GIT_NOREPO" ]; then
     if [ -d "${PROJECT}.git/" ]; then
         cd "${PROJECT}.git"
         if [ ! -d .git ]; then
@@ -53,6 +54,7 @@ else
         echo "Missing '${PROJECT}.git' directory!" >&2
         exit 1
     fi
+fi
 
 git_version=$(git describe --tags "${UPSTREAM_GIT_BRANCH}")
 package_version=$(echo "$git_version" | sed -e 's/^v//' -e 's/-/./g')