ci: use ubuntu-22.04 for local linux builds

[NickeZ]

This might fix the issue in the release github action.

edit:

At least it seems so with dist host --output-format=json

--- main.json   2025-06-09 12:32:16
+++ branch.json 2025-06-09 12:32:04
@@ -394,7 +394,7 @@
             "cache_provider": "github"
           },
           {
-            "runner": "ubuntu-20.04",
+            "runner": "ubuntu-22.04",
             "host": "x86_64-unknown-linux-gnu",
             "install_dist": {
               "shell": "sh",