CI: update action ubuntu build runners to 22.04 (#4847)

.github/workflows/build.yml

@@ -99,8 +99,8 @@ jobs:
           if-no-files-found: error
           retention-days: 7  # keep for 7 days, should be enough
 
-  build-ubuntu2004:
-    runs-on: ubuntu-20.04
+  build-ubuntu2204:
+    runs-on: ubuntu-22.04
     steps:
       # - copy code below to release.yml -
       - uses: actions/checkout@v4

.github/workflows/release.yml

@@ -29,8 +29,8 @@ jobs:
   # build-release-windows: # this is done by hand because of signing
   # build-release-macos: # LF volunteer
 
-  build-release-ubuntu2004:
-    runs-on: ubuntu-20.04
+  build-release-ubuntu2204:
+    runs-on: ubuntu-22.04
     steps:
       - name: Set env
         run: echo "RELEASE_VERSION=${GITHUB_REF#refs/*/}" >> $GITHUB_ENV