Add lockfile maintenance to dependabot pull request.

dependabot-bun-support-gitub-action.yml

on:
  push:
    branches:
      - main
  pull_request:
    types: [ opened, synchronize ]

name: Dependabot Bun Support

permissions:
  contents: write # to commit code (actions/checkout)

jobs:
  dependabot:
    runs-on: ubuntu-latest
    if: github.event.pull_request.user.login == 'dependabot[bot]'
    steps:
      - uses: actions/checkout@v3
        with:
          ref: ${{ github.event.pull_request.head.ref }}
      - uses: oven-sh/setup-bun@v1
        with:
          bun-version: latest
      - run: bun install
      - name: Set @github-actions[bot] as committer
        run: |
          git config --global user.name 'github-actions[bot]'
          git config --global user.email 'github-actions[bot]@users.noreply.github.com'
      - run: git status
      - run: git add -A
      - run: |
          git commit -m "chore(deps-dev): bump bun lockfile"
      - run: git push