using startswith to match PR title

Signed-off-by: Jaydip Gabani <[email protected]>

.github/workflows/tag.yaml

@@ -9,7 +9,7 @@ permissions:
 jobs:
   create_tag:
     name: "Create tag"
-    if: github.event.pull_request.merged == true && contains(github.event.pull_request.labels.*.name, 'release-pr') && contains(github.event.pull_request.title, format('chore{0} Prepare', ':'))
+    if: github.event.pull_request.merged == true && contains(github.event.pull_request.labels.*.name, 'release-pr') && startsWith(github.event.pull_request.title, format('chore{0} Prepare', ':'))
     runs-on: ubuntu-22.04
     steps:
     - name: "Set release tag"