[Bug] pulsar-admin namespaces set-retention not work

[labuladong]

Search before asking

• I searched in the issues and found nothing similar.

Version

Master version of Pulsar.

Minimal reproduce step

1. start stanalone Pulsar.
2. use pulsar-admin namespace set-retention then pulsar-admin namespace get-retention:

What did you expect to see?

Retention setting has changed.

What did you see instead?

Retention setting didn't change.

Anything else?

No response

Are you willing to submit a PR?

• I'm willing to submit a PR!

[labuladong]

This is not a cli bug, because the --size and --time need to specify a unit. The default is byte and second, so it will be considered as 0 if too small:

Usage: set-retention [options] tenant/namespace
  Options:
  * --size, -s
      Retention size limit with optional size unit suffix. For example, 4096,
      10M, 16G, 3T.  The size unit suffix character can be k/K, m/M, g/G, or
      t/T.  If the size unit suffix is not specified, the default unit is
      bytes. 0 or less than 1MB means no retention and -1 means infinite size
      retention
  * --time, -t
      Retention time with optional time unit suffix. For example, 100m, 3h,
      2d, 5w. If the time unit is not specified, the default unit is seconds.
      For example, -t 120 sets retention to 2 minutes. 0 means no retention
      and -1 means infinite time retention.

But the site document is wrong, so fix doc in #18526.