Update arm64 base job nodeset

With the move to zuul launchers we don't have bionic and focal arm64
images right now. The arm64 base test job attempts to check that we can
run our base roles against nodes of this type which fails with a
NODE_FAILURE. We don't actually run any nodes that old on arm64 anymore.
Everything (mirror and nodepool builder and our fake bridge) should all
be jammy or newer. Update the job to only run against jammy and noble as
a result.

Change-Id: I3e9c0c605c408d9776a5e3916a94f9e867474f73

zuul.d/system-config-run.yaml

@@ -154,12 +154,10 @@
     nodeset:
       nodes:
         - &bridge_node_arm64 { name: bridge99.opendev.org, label: ubuntu-jammy-arm64 }
-        - name: bionic
-          label: ubuntu-bionic-arm64
-        - name: focal
-          label: ubuntu-focal-arm64
         - name: jammy
           label: ubuntu-jammy-arm64
+        - name: noble
+          label: ubuntu-noble-arm64
       groups:
         - <<: *bastion_group
     files: