Anis Elleuch 5c765bc63e Fix one possible data race in admin tests (#6537)
go test shows the following warning:
```
WARNING: DATA RACE
Write at 0x000002909e18 by goroutine 276:
  github.com/minio/minio/cmd.testAdminCmdRunnerSignalService()
      /home/travis/gopath/src/github.com/minio/minio/cmd/admin-rpc_test.go:44 +0x94

 Previous read at 0x000002909e18 by goroutine 194:
  github.com/minio/minio/cmd.testServiceSignalReceiver()
      /home/travis/gopath/src/github.com/minio/minio/cmd/admin-handlers_test.go:467 +0x70
```

The reason for this data race is that some admin tests are not waiting for go routines
that they created to be properly exited, which triggers the race detector.
2018-09-27 17:16:30 -07:00
..
2018-06-06 14:21:56 +05:30
2018-06-06 14:21:56 +05:30
2018-09-18 16:46:35 -07:00