ci: Use also ubuntu 22.04 for release workflow

Author: metthal

.github/workflows/retdec-release.yml

@@ -19,7 +19,7 @@ jobs:
     strategy:
       matrix:
         sys:
-          - { os: ubuntu-latest, shell: bash }
+          - { os: ubuntu-22.04, shell: bash }
           - { os: windows-2019, shell: bash }
           - { os: macos-11, shell: bash }