Changes

ci(prow): migrate titan GHPR test to native presubmits (#4507)

## Background
This PR migrates the legacy Jenkins CI job
[titan_test](https://ci.pingcap.net/job/titan_ghpr_test/) to native Prow
presubmit jobs on GCP.

Issue Number: ref https://github.com/PingCAP-QE/ci/issues/4508

## Summary
- migrate the legacy titan GHPR Jenkins task to native Prow presubmit
jobs on GCP
- split the old parallel job into format, test, asan, tsan, ubsan,
release, and arm64 jobs

## Testing
- validated local pods in `prow-test-pods`
- `pull-titan-format`: passed
- `pull-titan-release`: passed
- `pull-titan-test`: passed
- `pull-titan-sanitizer-asan`: passed
- `pull-titan-sanitizer-tsan`: passed
- `pull-titan-sanitizer-ubsan`: passed
- `pull-titan-test-arm64`: passed

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Signed-off-by: lyb <yebin.li@pingcap.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
 (commit: da923c7)