[TASK] Shorten the GitHub Actions CI job label (#1646)

This makes the badge in the README shorter. Also, it makes it
easier to differentiate between the badge for GitHub Actions and
the one for GitLab CI.

.github/workflows/ci.yml

@@ -1,7 +1,7 @@
 ---
 # This GitHub Actions workflow uses the same development tools that are also installed locally
 # via Composer or PHIVE and calls them using the Composer scripts.
-name: CI with Composer scripts
+name: GitHub Actions CI
 on:
   push:
     branches: