Backport of Fix for loop in filter_changed_files_go_test script into release/1.15.x

.github/scripts/filter_changed_files_go_test.sh

@@ -19,7 +19,7 @@ files_to_check=$(git diff --name-only "$(git merge-base origin/$SKIP_CHECK_BRANC
 skipped_directories=("docs/" "ui/" "website/" "grafana/")
 
 # Loop through the changed files and find directories/files outside the skipped ones
-for file_to_check in $files_to_check; do
+for file_to_check in "${files_to_check[@]}"; do
 	file_is_skipped=false
 	for dir in "${skipped_directories[@]}"; do
 		if [[ "$file_to_check" == "$dir"* ]] || [[ "$file_to_check" == *.md && "$dir" == *"/" ]]; then