CI: Update to ubuntu-22.04 because ubuntu-20.04 is not supported

Author: ptpt

.github/workflows/release.yml

@@ -37,7 +37,10 @@ jobs:
           # Linux builds
           # When building with ubunutu-latest (24.04), we still see the following runtime error:
           # [PYI-4568:ERROR] Failed to load Python shared library '/tmp/_MEI3FR8Jx/libpython3.11.so.1.0': dlopen: /lib64/libm.so.6: version `GLIBC_2.38' not found (required by /tmp/_MEI3FR8Jx/libpython3.11.so.1.0)
-          - platform: ubuntu-20.04
+          #
+          # Update on 2025-04-01: Have to upgrade from 20.04 because:
+          # This is a scheduled Ubuntu 20.04 brownout. Ubuntu 20.04 LTS runner will be removed on 2025-04-15. For more details, see https://github.com/actions/runner-images/issues/11101
+          - platform: ubuntu-22.04
             os: linux
             architecture: x64
           - platform: 2-core-ubuntu-arm # or ubuntu-latest-arm