Remove irrelevant trigger from "Compose full changelog" workflow

The "Compose full changelog" GitHub Actions workflow generates a changelog file from the release notes and uploads this
to Arduino's server for display to the user by the IDE updater.

Previously, this workflow could be triggered by either of two events:

- Release creation
- Release edit

To reduce the possibility of endless recursion, GitHub Actions ignores events which are triggered using the
auto-generated `GITHUB_TOKEN` access token. All release creations are done automatically by the "Arduino IDE" GitHub
Actions workflow, which uses this token.

For this reason, the release creation trigger will never be used. Since the behavior of the event being ignored by
GitHub Actions under these conditions is not at all obvious, having the workflow configured for such an irrelevant
trigger can cause confusion.

The workflow will be triggered by the manual edit which is done on every release to format the raw release notes
auto-generated from the commit history. So the fact that the release creation trigger doesn't work is not a problem.

Author: per1234

Diff for: .github/workflows/compose-full-changelog.yaml

@@ -2,7 +2,8 @@ name: Compose full changelog
 
 on:
   release:
-    types: [created, edited]
+    types:
+      - edited
 
 env:
   CHANGELOG_ARTIFACTS: changelog