ci: Automate changelog generation

.github/workflows/generate-changelog.yml

@@ -0,0 +1,35 @@
+name: Generate changelog
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  # Generate a changelog
+  changelog:
+    name: Generate CHANGELOG.md
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Generate changelog file
+        run: |
+          # Temporary fix for https://github.com/actions/setup-go/issues/14
+          export PATH=$PATH:$(go env GOPATH)/bin
+          go get -u github.com/git-chglog/git-chglog/cmd/git-chglog
+          git-chglog -c .github/chglog/changelog.yml > CHANGELOG.md
+
+      - name: Push to GitHub
+        run: |
+          remote_repo="https://starship-bot:${CHANGELOG_GITHUB_TOKEN}@github.com/${GITHUB_REPOSITORY}.git"
+          git config user.name "Starship Bot"
+          git config user.email "bot@starship.rs"
+          git remote add publisher "${remote_repo}"
+          git show-ref # useful for debugging
+          git branch --verbose
+
+          git checkout master
+          git add -A
+          git commit -m "Update CHANGELOG.md [${GITHUB_SHA}]"
+          git pull --rebase publisher master
+          git push publisher master