feat: use regular ubuntu builder in CI.

Author: jrfaller

.github/workflows/build-test-gumtree.yml

@@ -18,7 +18,6 @@ concurrency:
 jobs:
   build-test-deploy:
     runs-on: ubuntu-24.04
-    container: gumtreediff/gumtree:latest
     environment: MavenCentral
     if: ${{ !(contains(github.event.head_commit.message, '[no ci]') || startsWith(github.event.head_commit.message, 'doc')) }}
     steps:
@@ -62,7 +61,7 @@ jobs:
           bodyFile: "CHANGELOG.md"
           token: ${{ secrets.GITHUB_TOKEN }}
   docker:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     needs: build-test-deploy
 
     if: ${{ (github.event_name == 'schedule' || github.event_name == 'workflow_dispatch') && !(contains(github.event.head_commit.message, '[no ci]') || startsWith(github.event.head_commit.message, 'doc')) }}