(CAT-2235) Troubleshoot failing nightlies

Currently, CI and nightlies are failing due to a JRuby installation issue.
This commit attempts to revert the provisioning ubuntu to an earlier version
to troubleshoot the issue.

Author: LukasAud

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ on:
 jobs:
   linux_tests:
     name: Linux, Puppet ${{ matrix.cfg.puppet_version }}, Ruby ${{ matrix.cfg.ruby }}
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       matrix:
         cfg:

.github/workflows/nightly.yml

@@ -7,7 +7,7 @@ on:
 jobs:
   linux_tests:
     name: Linux, Puppet ${{ matrix.cfg.puppet_version }}, Ruby ${{ matrix.cfg.ruby }}
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       matrix:
         cfg: