tiup dm display needs SSL support

[kzinas-adv]

Is your feature request related to a problem? Please describe

As it was discovred under pingcap/dm#2230, tiup-dm lack SSL support

Command:

 [root@dm-test-mst01 ~]# tiup dm display    test --ssh=system
Starting component `dm`: /root/.tiup/components/dm/v1.6.0/tiup-dm display test --ssh=system
Cluster type:       dm
Cluster name:       test
Cluster version:    v2.0.7
Deploy user:        root
SSH type:           builtin
ID             Role       Host      Ports      OS/Arch       Status  Data Dir                               Deploy Dir
--             ----       ----      -----      -------       ------  --------                               ----------
10.3.2.3:8261  dm-master  10.3.2.3  8261/8291  linux/x86_64  Down    /opt/tidb/dm/data-test/dm-master-8261  /opt/tidb/dm/deploy-test/dm-master-8261
10.3.2.2:8262  dm-worker  10.3.2.2  8262       linux/x86_64  N/A     /opt/tidb/dm/data-test/dm-worker-8262  /opt/tidb/dm/deploy-test/dm-worker-8262
Total nodes: 2
[root@dm-test-mst01 ~]# 

Logs:

 [2021/10/18 06:36:10.728 +00:00] [WARN] [config_logging.go:279] ["rejected connection"] [component="embed etcd"] [remote-addr=10.3.2.3:53700] [server-name=] [error="tls: first record does not look like a TLS handshake"]
[2021/10/18 06:36:12.105 +00:00] [WARN] [config_logging.go:279] ["rejected connection"] [component="embed etcd"] [remote-addr=10.3.2.3:53704] [server-name=] [error="tls: first record does not look like a TLS handshake"]
[2021/10/18 06:36:12.428 +00:00] [WARN] [config_logging.go:279] ["rejected connection"] [component="embed etcd"] [remote-addr=10.3.2.3:53706] [server-name=] [error="tls: first record does not look like a TLS handshake"]
[2021/10/18 06:36:20.183 +00:00] [INFO] [server.go:2206] [payload="op:Skip task:\"test\" "] [request=HandleError]
[2021/10/18 06:36:20.183 +00:00] [INFO] [server.go:2088] ["sources: [source1]"]
[2021/10/18 06:36:25.609 +00:00] [INFO] [server.go:2206] [payload="name:\"test\" "] [request=QueryStatus]
[2021/10/18 06:36:59.785 +00:00] [WARN] [config_logging.go:279] ["rejected connection"] [component="embed etcd"] [remote-addr=10.3.2.3:53726] [server-name=] [error="tls: first record does not look like a TLS handshake"]
[root@dm-test-mst01 log]# 

Describe the feature you'd like

tiup dm SSL support

Describe alternatives you've considered

Live without it

Teachability, Documentation, Adoption, Migration Strategy

No response

[nexustar]

pingcap/tiup#1745 Please help to review and test