Pin the Ubuntu runner to 22.04 to resolve CI failures.

This is due to ubuntu-latest was updated to 24.04 with Clang/LLVM 18, which is known to have issues with Abseil: llvm/llvm-project#102443

PiperOrigin-RevId: 713103399

Author: xinhaoyuan

.github/workflows/bazel_test.yml

@@ -27,7 +27,9 @@ on:
 jobs:
   run_tests:
     name: Run tests
-    runs-on: ubuntu-latest
+    # TODO(xinhaoyuan): Bump to 24.04 after https://github.com/llvm/llvm-project/issues/102443
+    # is fixed.
+    runs-on: ubuntu-22.04
     timeout-minutes: 60
     strategy:
       matrix:

.github/workflows/bazel_test_centipede.yml

@@ -27,7 +27,9 @@ on:
 jobs:
   run_tests:
     name: Run Centipede tests
-    runs-on: ubuntu-latest
+    # TODO(xinhaoyuan): Bump to 24.04 after https://github.com/llvm/llvm-project/issues/102443
+    # is fixed.
+    runs-on: ubuntu-22.04
     timeout-minutes: 60
     strategy:
       matrix:

.github/workflows/cmake_test.yml

@@ -27,7 +27,9 @@ on:
 jobs:
   run_tests:
     name: Run CMake tests
-    runs-on: ubuntu-latest
+    # TODO(xinhaoyuan): Bump to 24.04 after https://github.com/llvm/llvm-project/issues/102443
+    # is fixed.
+    runs-on: ubuntu-22.04
     timeout-minutes: 30
     env:
       CCACHE_BASEDIR: ${{ github.workspace }}