Update CI to run on non-deprecated Ubuntu versions

Author: pimterry

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ jobs:
         include:
           - platform: linux
             arch: x64
-            os: "ubuntu-20.04"
+            os: "ubuntu-22.04"
           - platform: linux
             arch: arm64
             os: "ubuntu-24.04-arm"
@@ -71,7 +71,7 @@ jobs:
           if-no-files-found: error
   publish:
     name: Publish a release
-    runs-on: "ubuntu-20.04"
+    runs-on: "ubuntu-22.04"
     if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
     needs: build
     steps: