replace set-output command with github env var

.github/workflows/lint-migrations.yml

@@ -16,8 +16,7 @@ jobs:
         run: |
           modified_migrations=$(git diff --diff-filter=d --name-only main 'packages/db/migrations/*.do.*.sql')
           echo "$modified_migrations"
-          echo "::set-output name=file_names::$modified_migrations"
-        id: modified-migrations
+          echo "{FILE_NAMES}={$modified_migrations}" >> $GITHUB_OUTPUT
       - uses: sbdchd/squawk-action@v1
         with:
-          pattern: ${{ steps.modified-migrations.outputs.file_names }}
+          pattern: $FILE_NAMES