Updated ubuntu test versions

Author: kurtkilpelags

.github/workflows/ci.yml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ ubuntu-20.04, macos-latest ]
+        os: [ ubuntu-22.04, ubuntu-latest, macos-latest ]
         smalltalk: [ GemStone64-3.7.1, GemStone64-3.6.8, GemStone64-3.5.8 ]
         exclude: 
           - smalltalk: GemStone64-3.5.8
@@ -36,7 +36,7 @@ jobs:
     name: Post Workflow Status To Slack
     needs:
       - build
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
        - name: Slack Workflow Notification
          uses: Gamesight/slack-workflow-status@master