TestConcurrentlyReset is unstable

## Flaky Test

### Which jobs are failing
```
2023-08-04T10:00:27.2580986Z === RUN TestMicroserviceTSOServer/TestConcurrentlyReset
2023-08-04T10:00:27.2583758Z [2023/08/04 10:00:27.258 +00:00] [INFO] [handler.go:37] [reset-ts] [new-ts=443323050166321152] [ignore-smaller=false] [skip-upper-bound-check=false] [keyspace-group-id=0]
2023-08-04T10:00:27.2653657Z [2023/08/04 10:00:27.265 +00:00] [INFO] [handler.go:37] [reset-ts] [new-ts=443323050166321152] [ignore-smaller=false] [skip-upper-bound-check=false] [keyspace-group-id=0]
2023-08-04T10:00:27.2657681Z server_test.go:115:
2023-08-04T10:00:27.2658891Z Error Trace: /home/runner/work/pd/pd/tests/integrations/tso/server_test.go:115
2023-08-04T10:00:27.2660538Z /home/runner/work/pd/pd/tests/integrations/tso/server_test.go:161
2023-08-04T10:00:27.2661801Z /opt/hostedtoolcache/go/1.20.1/x64/src/runtime/asm_amd64.s:1598
2023-08-04T10:00:27.2663310Z Error: Error "[PD:tso:ErrResetUserTimestamp]reset user timestamp failed, the specified ts is too larger than now" does not contain "is smaller than now"
2023-08-04T10:00:27.2664548Z Test: TestMicroserviceTSOServer/TestConcurrentlyReset
2023-08-04T10:00:27.2665513Z server_test.go:115:
2023-08-04T10:00:27.2666398Z Error Trace: /home/runner/work/pd/pd/tests/integrations/tso/server_test.go:115
2023-08-04T10:00:27.2667977Z /home/runner/work/pd/pd/tests/integrations/tso/server_test.go:161
2023-08-04T10:00:27.2669182Z /opt/hostedtoolcache/go/1.20.1/x64/src/runtime/asm_amd64.s:1598
2023-08-04T10:00:27.2670665Z Error: Error "[PD:tso:ErrResetUserTimestamp]reset user timestamp failed, the specified ts is too larger than now" does not contain "is smaller than now"
2023-08-04T10:00:27.2671654Z Test: TestMicroserviceTSOServer/TestConcurrentlyReset
```

### CI link

https://github.com/tikv/pd/actions/runs/5760861853/job/15617635075?pr=6888
### Reason for failure (if possible)

### Anything else