Build/test for Python 3.7 on ubuntu-22.04.

Python 3.7 is not available in current ubuntu-latest (ubuntu-24.04).

https://github.com/hbldh/pybankid/actions/runs/12830165572/job/35777723516?pr=78

Author: Majsvaffla

.github/workflows/build_and_test.yml

@@ -18,7 +18,10 @@ jobs:
         strategy:
             matrix:
                 os: [ubuntu-latest]
-                python-version: [3.7, 3.8, 3.9, '3.10', '3.11', '3.12']
+                python-version: [3.8, 3.9, '3.10', '3.11', '3.12']
+                include:
+                    -   os: ubuntu-22.04
+                        python-version: 3.7
         steps:
             -   uses: actions/checkout@v4