update workflow to run ubuntu 22.04 instead of 20.04

Author: k0ka

.github/workflows/integration_tests.yml

@@ -36,13 +36,13 @@ jobs:
             ubuntu_version: "22.04"
           - name: "zed"
             openstack_version: "unmaintained/zed"
-            ubuntu_version: "20.04"
+            ubuntu_version: "22.04"
           - name: "yoga"
             openstack_version: "unmaintained/yoga"
-            ubuntu_version: "20.04"
+            ubuntu_version: "22.04"
           - name: "wallaby"
             openstack_version: "unmaintained/wallaby"
-            ubuntu_version: "20.04"
+            ubuntu_version: "22.04"
             block_storage_v2: true
     runs-on: ubuntu-${{ matrix.ubuntu_version }}
     name: Deploy OpenStack ${{ matrix.name }} and run integration tests with php ${{matrix.php_version}}