docs/data/reusables/actions/workflows/triggering-workflow-branches3.md

When a pattern matches the branches-ignore pattern, the workflow will not run. The patterns defined in branches-ignore are evaluated against the Git ref's name. For example, the following workflow would run whenever there is a pull_request event unless the pull request is targeting:

• A branch named mona/octocat (refs/heads/mona/octocat)
• A branch whose name matches releases/**-alpha, like releases/beta/3-alpha (refs/heads/releases/beta/3-alpha)

on:
  pull_request:
    # Sequence of patterns matched against refs/heads
    branches-ignore:
      - 'mona/octocat'
      - 'releases/**-alpha'