Stop using deprecated OS

Author: drwetter

.github/workflows/test.yml

@@ -32,7 +32,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: ['ubuntu-20.04']
+        os: ['ubuntu-22.04']
         perl: ['5.26']
     name: Perl ${{ matrix.perl }} on ${{ matrix.os }}
     steps: