switch to random suffix, we can have more PRs based on same hash

Author: martenson

.github/workflows/dispatch_update.yml

@@ -61,7 +61,7 @@ jobs:
         uses: peter-evans/create-pull-request@v7
         with:
           branch: create-pull-request/update
-          branch-suffix: short-commit-hash
+          branch-suffix: random
           committer: CESNETbot <[email protected]>
           commit-message: ${{ steps.vars.outputs.pr_title }}
           title: ${{ steps.vars.outputs.pr_title }}