feat(ci): add commits check to CI

Closes bitcoindevkit#1119.
Creates `commits.yml` in `.github/workflows/` directory with a new GH Action
that has 2 jobs:

1. `signed-commits`: uses [`1Password/check-signed-commits-action`](https://github.com/1Password/check-signed-commits-action)
   to check if all commits in the PR are signed.
1. `conventional-commits`: uses [`cocogitto/cocogitto-action`](https://github.com/cocogitto/cocogitto-action)
   based on [`cocogitto`](https://crates.io/crates/cocogitto)
   to check if all commits in the PR follows the conventional commits](https://www.conventionalcommits.org/en/v1.0.0-beta.2/),
   i.e. they are prefixed with `fix`, `refactor`, `feat` etc.

.github/workflows/commits.yml

@@ -0,0 +1,26 @@
+name: Check Commits
+
+on:
+ pull_request:
+ branches: master
+
+jobs:
+ signed-commits:
+ name: Check signed commits in PR
+ runs-on: ubuntu-latest
+ steps:
+ - uses: actions/checkout@v4
+ - name: Check signed commits in PR
+ uses: 1Password/check-signed-commits-action@v1
+ conventional-commits:
+ name: Conventional Commits
+ runs-on: ubuntu-latest
+ steps:
+ - uses: actions/checkout@v4
+ with:
+ # needs the full log
+ fetch-depth: 0
+ # pick the pr HEAD instead of the merge commit
+ ref: ${{ github.event.pull_request.head.sha }}
+ - name: Check conventional commits in PR
+ uses: cocogitto/cocogitto-action@v3