improve bash for consistency

Co-authored-by: Tarun Kumar <takumar@redhat.com>

Author: derekk-nm

actions/reportportal_submit_execution_results/action.yml

@@ -71,7 +71,7 @@ runs:
 
         # generate report metadata file
         TEMPLATE="${GITHUB_ACTION_PATH}/droute_send_template.json"
-        if [ ! -f $TEMPLATE ]; then
+        if [[ ! -f "$TEMPLATE" ]]; then
           echo "droute_send_template.json not found in $GITHUB_ACTION_PATH"
           exit 1
         fi