remove tab

Author: Vladimir Kotal

.github/workflows/docker.yml

@@ -12,5 +12,5 @@ jobs:
       env:
         OPENGROK_REPO_SLUG: ${{ github.repository }}
         OPENGROK_PULL_REQUEST: ${{ github.head_ref }}
-	OPENGROK_REF: ${{ github.ref }}
+        OPENGROK_REF: ${{ github.ref }}
       run: ./dev/docker.sh