Run test on ubuntu-22.04

Author: unasuke

.github/workflows/test.yml

@@ -9,7 +9,7 @@ on:
     - cron: "0 0 * * 6" # At 00:00 on Saturday
 jobs:
   test:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     strategy:
       matrix:
         ruby: ["3.2", "3.1", "3.0", "2.7", "2.6"]