docs(RELEASE): omit minor version in branch name

Author: ErichDonGubler

docs/release-checklist.md

@@ -46,7 +46,7 @@ Day of Release:
     cargo publish -p wgpu-info
   ```
 - Create a new release on the `wgpu` repo with the changelog and a tag called `vX.Y.Z`.
-- Create a branch with the with the new version `vX.Y` and push it to the repo.
+- Create a branch with the with the new version `vX` and push it to the repo.
 - Publish the link to the github release in the following places.
   - [r/rust](https://www.reddit.com/r/rust/).
     - Add an AMA comment.