fix: exit 0 with empty output when no files are provided (#16)

A PR that only deletes files produces no entries in all_changed_files,
resulting in empty input. This is a valid state — treat it as no
projects to build rather than an error.

Co-authored-by: Ansel Robateau <ansel.robateau@redshelf.com>

Author: robaone

scripts/parse_file_list_for_projects.sh

@@ -9,8 +9,7 @@
 INPUT="$(cat)"
 
 if [ "$INPUT" == "" ]; then
-  echo "You must provide a list of files"
-  exit 1
+  exit 0
 fi
 
 if [ "$GIT_CMD" == "" ]; then