release-drafter (#33)

The auxiliary GH action to setup release drafts and update change log
accordingly. Configured with autolabeler, so the PRs will be labeled
according to the PR branch name and/or files changed:

| Branch name  | Files changed | Resulting label |
| ------------- | ------------- | ------------- |
| deps/*  |  | `dependencies`  |
| chore/*  |  | `chore`  |
| docs/* | **/*.md | `documentation` |
| enh/* |  | `enhancement` |
| feature/* |  | `feature` |
| fix/* |  | `bugfix` |
| bugfix/* |  | `bugfix` |
|  | /api/* | `api-change` |
|  | /internal/* | `controllers` |

Based on labels release draft will be updated with 'Features', 'Bug
Fixes' and 'Maintenance' categories which will include corresponding
PR's title.
It's also possible to manage release draft's version by applying
`major`, `minor` and `patch` labels on PR. By default the version will
be the next patch version after the last release, v0.0.1 if none.

---------

Signed-off-by: Artem Bortnikov <artem.bortnikov@telekom.com>

.github/release-drafter.yml

@@ -0,0 +1,61 @@
+name-template: 'v$RESOLVED_VERSION'
+tag-template: 'v$RESOLVED_VERSION'
+categories:
+  - title: 'Features'
+    labels:
+      - 'feature'
+      - 'enhancement'
+  - title: 'Bug Fixes'
+    labels:
+      - 'bugfix'
+  - title: 'Maintenance'
+    labels:
+      - 'chore'
+      - 'dependencies'
+      - 'documentation'
+change-template: '- $TITLE @$AUTHOR (#$NUMBER)'
+change-title-escapes: '\<*_&' # You can add # and @ to disable mentions, and add ` to disable code blocks.
+version-resolver:
+  major:
+    labels:
+      - 'major'
+  minor:
+    labels:
+      - 'minor'
+  patch:
+    labels:
+      - 'patch'
+  default: patch
+exclude-labels:
+  - 'skip-changelog'
+autolabeler:
+  - label: 'api-change'
+    files:
+      - '/api/*'
+  - label: 'controllers'
+    files:
+      - '/internal/*'
+  - label: 'bugfix'
+    branch:
+      - '/fix\/.+/'
+      - '/bugfix\/.+/'
+  - label: 'feature'
+    branch:
+      - '/feature\/.+/'
+  - label: 'enhancement'
+    branch:
+      - '/enh\/.+/'
+  - label: 'chore'
+    branch:
+      - '/chore\/.+/'
+  - label: 'dependencies'
+    branch:
+      - '/deps\/.+/'
+  - label: 'documentation'
+    files:
+      - '**/*.md'
+    branch:
+      - '/docs\/.+/'
+template: |
+  ## Changes
+  $CHANGES

.github/workflows/release-drafter.yml

@@ -0,0 +1,18 @@
+name: Release Drafter
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - main
+
+jobs:
+  update_release_draft:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: release-drafter/release-drafter@v6
+        with:
+          disable-releaser: github.ref != 'refs/heads/main'
+          config-name: release-drafter.yml
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}