CI: Kill CI Test after 2 hours

CI Test will sometimes run for 6 hours (before getting auto-terminated by GitHub):
- #14808
- #14680

This is a problem because:
- It will increase our usage of GitHub Runners. Which may overrun the [GitHub Actions Budget](https://infra.apache.org/github-actions-policy.html) allocated by ASF.
- Suppose right after CI Test there's another build. If CI Test runs for all 6 hours, then the build after CI Test will never run.

For this PR: We assume that Every CI Job (e.g. risc-v-05) will complete normally within 2 hours. If any CI Job exceeds 2 hours: This PR will kill the CI Test Process `pytest` and allow the next build to run.

.github/workflows/build.yml

@@ -184,6 +184,7 @@ jobs:
             if [ "X${{matrix.boards}}" = "Xcodechecker" ]; then
                 ./cibuild.sh -c -A -N -R --codechecker testlist/${{matrix.boards}}.dat
             else
+                ( sleep 7200 ; echo Killing pytest after timeout... ; pkill -f pytest )&
                 ./cibuild.sh -c -A -N -R -S testlist/${{matrix.boards}}.dat
             fi