Occurs data race in CI

[chunshao90]

Describe this problem Occurs data race in CI

==================
WARNING: DATA RACE
Write at 0x00c00033f4d0 by goroutine 115:
  github.com/CeresDB/ceresmeta/server/member.TestWatchLeaderSingle()
      /home/runner/work/ceresmeta/ceresmeta/server/member/watch_leader_test.go:56 +0x572
  testing.tRunner()
      /opt/hostedtoolcache/go/1.19.3/x64/src/testing/testing.go:1446 +0x216
  testing.(*T).Run.func1()
      /opt/hostedtoolcache/go/1.19.3/x64/src/testing/testing.go:1493 +0x47

Previous read at 0x00c00033f4d0 by goroutine 169:
  github.com/CeresDB/ceresmeta/server/member.TestWatchLeaderSingle.func1()
      /home/runner/work/ceresmeta/ceresmeta/server/member/watch_leader_test.go:48 +0x44

Goroutine 115 (running) created at:
  testing.(*T).Run()
      /opt/hostedtoolcache/go/1.19.3/x64/src/testing/testing.go:1493 +0x75d
  testing.runTests.func1()
      /opt/hostedtoolcache/go/1.19.3/x64/src/testing/testing.go:1846 +0x99
  testing.tRunner()
      /opt/hostedtoolcache/go/1.19.3/x64/src/testing/testing.go:1446 +0x216
  testing.runTests()
      /opt/hostedtoolcache/go/1.19.3/x64/src/testing/testing.go:1844 +0x7ec
  testing.(*M).Run()
      /opt/hostedtoolcache/go/1.19.3/x64/src/testing/testing.go:1726 +0xa84
  main.main()
      _testmain.go:101 +0x3bc

Goroutine [169](https://github.com/CeresDB/ceresmeta/actions/runs/3540880881/jobs/5945078085#step:4:170) (running) created at:
  github.com/CeresDB/ceresmeta/server/member.TestWatchLeaderSingle()
      /home/runner/work/ceresmeta/ceresmeta/server/member/watch_leader_test.go:47 +0x519
  testing.tRunner()
      /opt/hostedtoolcache/go/1.19.3/x64/src/testing/testing.go:1446 +0x216
  testing.(*T).Run.func1()
      /opt/hostedtoolcache/go/1.19.3/x64/src/testing/testing.go:1493 +0x47

Steps to reproduce

Expected behavior

Additional Information