Klaus Post 2680772d4b
Don't mark remotes online when shutting down (#11368)
Shutting down will mark remotes online when the shutdown has 
started since the context is canceled.

For example:

```
API: SYSTEM()
Time: 16:21:31 CET 01/28/2021
DeploymentID: 313b0065-c5a1-4aa3-9233-07223e77a730
Error: Storage resources are insufficient for the write operation .minio.sys/tmp/ced455c4-3d27-4bdd-95fc-b4707a179b8a/fd934ef3-8fc8-4330-abc1-f039fbbb9700/part.1 (cmd.InsufficientWriteQuorum)
       1: d:\minio\minio\cmd\data-usage.go:56:cmd.storeDataUsageInBackend()
Exiting on signal: INTERRUPT
Client http://127.0.0.1:9002/minio/lock/v5 online
Client http://127.0.0.1:9002/minio/storage/data/distxl/s2/d3/v24 online
Client http://127.0.0.1:9002/minio/storage/data/distxl/s2/d2/v24 online
Client http://127.0.0.1:9002/minio/storage/data/distxl/s2/d1/v24 online
Client http://127.0.0.1:9002/minio/peer/v12 online
Client http://127.0.0.1:9002/minio/storage/data/distxl/s2/d4/v24 online
```

Use a fresh context for health checks.
2021-01-28 13:38:12 -08:00
..
2021-01-26 20:47:42 -08:00
2020-01-31 08:29:22 +05:30
2021-01-18 20:35:38 -08:00