updated ubuntu from 18.04 (unsupported) to 22.04

Author: mike-gangl

.github/workflows/python-app.yml

@@ -18,7 +18,7 @@ jobs:
         python-version: [ "3.9", "3.10" ]
         poetry-version: [ "1.1.14" ]
         # os: [ ubuntu-18.04, macos-latest, windows-latest ]
-        os: [ ubuntu-18.04, macos-latest ]
+        os: [ ubuntu-22.04, macos-latest ]
     runs-on: ${{ matrix.os }}
     steps:
     - uses: actions/checkout@v2