ci: fix missing environment var in scheduled builds

remove reference to a removed environment variable. as the workflow runs on the current repo, it shouldn't be needed.

.github/workflows/schedule-trigger.yml

@@ -61,7 +61,7 @@ jobs:
         shell: bash
         #language=bash
         run: |
-          gh workflow run --repo "$REPOSITORY" "$WORKFLOW_NAME.yml"
+          gh workflow run "$WORKFLOW_NAME.yml"
 
           echo "Job '$WORKFLOW_NAME' dispatched."