[actions] in .github/workflows/testsuite_oneprocess.yml, temporarely …

…downgrade ubuntu-latest to ubuntu-22.04 because clang-format-18 is not yet supported (madgraph5#1022)

Note: ubuntu-24.04 images are available since three weeks ago (processone/ejabberd issues/4281)

.github/workflows/testsuite_oneprocess.yml

@@ -45,7 +45,10 @@ jobs:
   # See https://github.com/actions/cache/blob/main/tips-and-workarounds.md#force-deletion-of-caches-overriding-default-cache-eviction-policy
   cleanup:
     ###if: ${{ false }} # disable the job (comment this out to enable it!)
-    runs-on: ubuntu-latest
+    # Temporarely dowgrade ubuntu-latest to ubuntu-22.04 because clang-format-18 is not yet supported (#1022)
+    # See https://github.com/actions/runner-images/issues/5490
+    ###runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     permissions:
       actions: write # this is required to delete caches
       contents: read