Fix globalDeploymentID race (#18275)

globalDeploymentID was being read while it was being set.

Fixes race:

```
WARNING: DATA RACE
Write at 0x0000079605a0 by main goroutine:
  github.com/minio/minio/cmd.connectLoadInitFormats()
      github.com/minio/minio/cmd/prepare-storage.go:269 +0x14f0
  github.com/minio/minio/cmd.waitForFormatErasure()
      github.com/minio/minio/cmd/prepare-storage.go:294 +0x21d
...

Previous read at 0x0000079605a0 by goroutine 105:
  github.com/minio/minio/cmd.newContext()
      github.com/minio/minio/cmd/utils.go:817 +0x31e
  github.com/minio/minio/cmd.adminMiddleware.func1()
      github.com/minio/minio/cmd/admin-router.go:110 +0x96
  net/http.HandlerFunc.ServeHTTP()
      net/http/server.go:2136 +0x47
  github.com/minio/minio/cmd.setBucketForwardingMiddleware.func1()
      github.com/minio/minio/cmd/generic-handlers.go:460 +0xb1a
  net/http.HandlerFunc.ServeHTTP()
      net/http/server.go:2136 +0x47
...
```

cmd/api-response.go

@@ -978,7 +978,7 @@ func writeCustomErrorResponseJSON(ctx context.Context, w http.ResponseWriter, er
 		BucketName: reqInfo.BucketName,
 		Key:        reqInfo.ObjectName,
 		RequestID:  w.Header().Get(xhttp.AmzRequestID),
-		HostID:     globalDeploymentID,
+		HostID:     globalDeploymentID(),
 	}
 	encodedErrorResponse := encodeResponseJSON(errorResponse)
 	writeResponse(w, err.HTTPStatusCode, encodedErrorResponse, mimeJSON)