[CHORE] update github release workflow to specify draft in the title

[wileyj]

ref: https://github.com/stacks-network/stacks-core/blob/master/.github/workflows/github-release.yml#L75

for the release title, since we're creating a release in draft mode and requiring a manual step to update, we should title the release accordingly. ex: [DRAFT] Release 3.1.0.0.4

[wileyj]

Additionally, since we edit the release description to include the changelog, it may make sense to remove the "what's changed" with each PR itemized.