Update runners to ubuntu-24.04 from deprecated ubuntu-20.04 label (#2142)

Co-authored-by: Bill Napier <napier@google.com>

Author: google-admin

.github/workflows/build.arm64.yml

@@ -71,7 +71,7 @@ jobs:
   release-macos-arm64:
     name: Release (MacOS arm64)
     needs: macos-arm64-wheel
-    runs-on: ubuntu-20.04
+    runs-on: 'ubuntu-24.04'
     steps:
       - uses: actions/download-artifact@65a9edc5881444af0b9093a5e628f2fe47ea3b2e # v4.1.7
         with:
@@ -106,7 +106,7 @@ jobs:
   release-candidate-macos-arm64:
     name: Release Candidate (MacOS arm64)
     needs: release-macos-arm64
-    runs-on: ubuntu-20.04
+    runs-on: 'ubuntu-24.04'
     steps:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
       - uses: actions/download-artifact@65a9edc5881444af0b9093a5e628f2fe47ea3b2e # v4.1.7