change it to support run in branch

Signed-off-by: juicer <[email protected]>

.github/workflows/build-fb-image.yaml

@@ -21,6 +21,7 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@v4
+        ref: ${{ github.ref }}
 
       - name: Read fluent-bit version from file
         id: get-version