Fix backport skip condition

Author: flobernd

.github/workflows/backport.yml

@@ -8,7 +8,7 @@ jobs:
   backport:
     name: Backport PR
     runs-on: ubuntu-latest
-    if: github.event.pull_request.merged == true && !(contains(github.event.pull_request.labels.*.name, 'backport-'))
+    if: github.event.pull_request.merged == true && !(contains(github.event.pull_request.labels.*.name, 'backport'))
 
     steps:
       - name: Backport