fix(ci): don't cancel a release that is already running

Dispatching the release workflow again for the same tag cancelled the
running release, which could stop it in the middle of uploading assets
and leave the release with only some of them. Queue the new run behind
the running one instead.

.github/workflows/release.yml

@@ -13,7 +13,8 @@ permissions:
 
 concurrency:
   group: "${{ github.workflow }}-${{ github.event.inputs.release-tag }}"
-  cancel-in-progress: true
+  # Let a running release finish, so its assets are never left partially uploaded.
+  cancel-in-progress: false
 
 jobs:
   release: