Show components does not show all taskmanager

**Bug Description**

Now users deploy three taskmanager but only show one taskmanager with command `show components`.

```
10.38.121.16:7527/> show components;
-------------------- ------------- --------------------- -------- ---------
Endpoint Role Connect_time Status Ns_role
-------------------- ------------- --------------------- -------- ---------
10.38.121.16:10921 tablet 2024-01-04 16:43:09 online NULL
10.38.121.17:10921 tablet 2024-01-04 16:43:09 online NULL
10.38.121.18:10921 tablet 2024-01-04 16:43:09 online NULL
10.38.121.16:7527 nameserver 2024-01-04 16:43:10 online master
10.38.121.17:7527 nameserver 2024-01-04 16:44:59 online standby
10.38.121.18:7527 nameserver 2024-01-04 16:45:47 online standby
10.38.121.16:9902 taskmanager 2024-01-04 17:06:21 online NULL
-------------------- ------------- --------------------- -------- ---------
```

**Expected Behavior**

Show all standby taskmanagers in command line.

The 'show components' command output is missing two taskmanagers. Look for the SQL command handler in the codebase, likely in a nameserver or CLI component. Find where the component list is assembled and filtered. Check if there's a condition that incorrectly excludes standby taskmanagers. Verify by running the command in a test environment after making changes.

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