meta: Update instructions on release process (#4755)

Author: sentrivana

CONTRIBUTING.md

@@ -138,18 +138,18 @@ _(only relevant for Python SDK core team)_
 
 - On GitHub in the `sentry-python` repository, go to "Actions" and select the "Release" workflow.
 - Click on "Run workflow" on the right side, and make sure the `master` branch is selected.
-- Set the "Version to release" input field. Here you decide if it is a major, minor or patch release. (See "Versioning Policy" below)
+- Set the "Version to release" input field. Here you decide if it is a major, minor or patch release (see "Versioning Policy" below).
 - Click "Run Workflow".
 
-This will trigger [Craft](https://github.com/getsentry/craft) to prepare everything needed for a release. (For more information, see [craft prepare](https://github.com/getsentry/craft#craft-prepare-preparing-a-new-release).) At the end of this process a release issue is created in the [Publish](https://github.com/getsentry/publish) repository. (Example release issue: https://github.com/getsentry/publish/issues/815)
+This will trigger [Craft](https://github.com/getsentry/craft) to prepare everything needed for a release. (For more information, see [craft prepare](https://github.com/getsentry/craft#craft-prepare-preparing-a-new-release).) At the end of this process a release issue is created in the [Publish](https://github.com/getsentry/publish) repository (example issue: https://github.com/getsentry/publish/issues/815).
 
-Now one of the persons with release privileges (most probably your engineering manager) will review this issue and then add the `accepted` label to the issue.
+At the same time, the action will create a release branch in the `sentry-python` repository called `release/<version>`. You may want to check out this branch and polish the auto-generated `CHANGELOG.md` before proceeding by including code snippets, descriptions, reordering and reformatting entries, in order to make the changelog as useful and actionable to users as possible.
 
-There are always two persons involved in a release.
+CI must be passing on the release branch; if there's any failure, Craft will not create a release.
 
-If you are in a hurry and the release should be out immediately, there is a Slack channel called `#proj-release-approval` where you can see your release issue and where you can ping people to please have a look immediately.
+Once the release branch is ready and green, notify your team (or your manager). They will need to add the `accepted` label to the issue in the `publish` repo. There are always two people involved in a release. Do not accept your own releases.
 
-When the release issue is labeled `accepted`, [Craft](https://github.com/getsentry/craft) is triggered again to publish the release to all the right platforms. (See [craft publish](https://github.com/getsentry/craft#craft-publish-publishing-the-release) for more information.) At the end of this process the release issue on GitHub will be closed and the release is completed! Congratulations!
+When the release issue is labeled `accepted`, [Craft](https://github.com/getsentry/craft) is triggered again to publish the release to all the right platforms. See [craft publish](https://github.com/getsentry/craft#craft-publish-publishing-the-release) for more information. At the end of this process, the release issue on GitHub will be closed and the release is completed! Congratulations!
 
 There is a sequence diagram visualizing all this in the [README.md](https://github.com/getsentry/publish) of the `Publish` repository.