ci(foundation): 所有job改用saas专用标签，隔离actions测试任务

- 所有7个CI job从ubuntu-22.04改为saas标签
- auto-merge从ubuntu-latest改为saas标签
- runner只保留saas和runtime-builder标签
- 彻底隔离第三方actions的测试任务，保障业务流水线资源

.gitea/workflows/auto-merge.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   auto-merge:
-    runs-on: ubuntu-latest
+    runs-on: saas
     timeout-minutes: 10
     steps:
       - name: Checkout code

.gitea/workflows/ci-cd.yml

@@ -22,7 +22,7 @@ permissions:
 jobs:
   validate:
     name: Validate Code Quality And Tests
-    runs-on: ubuntu-22.04
+    runs-on: saas
     timeout-minutes: 10
 
     env:
@@ -198,7 +198,7 @@ jobs:
 
   frontend-lint:
     name: Frontend Lint
-    runs-on: ubuntu-22.04
+    runs-on: saas
     timeout-minutes: 10
 
     steps: