Switch to simple upstream releases

This commit changes our release process from the model of having a
release commit (and pull request) which also updated the NEWS.md file
and bumped the versions in the osbuild.spec and setup.py files to simply
pushing a tag.

After the tag (containing the release notes) is pushed, a GitHub
composite action is triggered that creates a GitHub release with the
contents of the git release tag. Furthermore the bumping of the version
number now always has to happen directly after a release to avoid having
to push a(n untested) commit to main for the release and this is also
handled by the GitHub composite action.

Finally packit pushes directly to dist-git now on pushing the release
tag, so no pull-request needs to be reviewed and merged anymore.

Consequently, we also drop the docs/news folder and its content and
adjust the PR template.

.github/PULL_REQUEST_TEMPLATE.md

@@ -3,7 +3,6 @@ This pull request includes:
 
 - [ ] adequate testing for the new functionality or fixed issue
 - [ ] adequate documentation informing people about the change such as
-  - [ ] create a file in [news/unreleased](https://github.com/osbuild/osbuild-composer/tree/main/docs/news/unreleased) directory if this change should be mentioned in the release news
   - [ ] submit a PR for the [guides](https://github.com/osbuild/guides) repository if this PR changed any behavior described there: https://www.osbuild.org/guides/
 
 <!--
@@ -16,9 +15,6 @@ anything.
 If the reason for ticking any of the boxes is ambiguous, please add a short
 note explaining why.
 
-For user-visible changes, "adequate documentation" is an entry describing the
-change for users in docs/news. Please refer to docs/news/README.md for details.
-
 In addition, if this pull request fixes a downstream issue, please refer to
 test/README.md and add these additional items:
 

.github/workflows/release.yml

@@ -0,0 +1,15 @@
+name: "Create GitHub release"
+
+on:
+  push:
+    tags:
+      - "v*"
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Upstream release
+        uses: osbuild/release-action@main
+        with:
+          token: "${{ secrets.GITHUB_TOKEN }}"