Workflow permission is required for pushing changes

[achyutjhunjhunwala]

When setting up the PAT, we also need workflow permission and not just repo permissions as mentioned in the docs

{"level":"info","message":"Results","metadata":{"0":{"error":{"context":{"cmdArgs":["push","achyutjhunjhunwala","backport/8.7/pr-153290:backport/8.7/pr-153290","--force"],"code":1,"stderr":"To https://github.com/achyutjhunjhunwala/kibana.git\n ! [remote rejected]         backport/8.7/pr-153290 -> backport/8.7/pr-153290 (refusing to allow a Personal Access Token to create or update workflow `.github/workflows/add-to-imui-project.yml` without `workflow` scope)\nerror: failed to push some refs to 'https://github.com/achyutjhunjhunwala/kibana.git'\n","stdout":""},"name":"SpawnError"},"status":"unhandled-error","targetBranch":"8.7"}},"timestamp":"2023-03-20 15:32:07"}