CI: Use 22.04 until antsee stable

Author: wsnyder

.github/workflows/build.yml

@@ -18,11 +18,11 @@ permissions:
 
 jobs:
   vlt:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-22.04
     name: build and test
     env:
       CI_OS_NAME: linux
-      CI_RUNS_ON: ubuntu-24.04
+      CI_RUNS_ON: ubuntu-22.04
       CI_COMMIT: ${{ github.sha }}
       CCACHE_COMPRESS: 1
       CCACHE_DIR: ${{ github.workspace }}/.ccache
@@ -65,6 +65,7 @@ jobs:
           CI_BUILD_STAGE_NAME: test
         run: |
           cd submodules/verilator && bash ci/ci-install.bash
+          PIP_BREAK_SYSTEM_PACKAGES=1 sudo pip install --upgrade pip
           PIP_BREAK_SYSTEM_PACKAGES=1 sudo pip install ../astsee
 
       - name: Test