Remove error message referencing issue 8173 since it's fixed

[AlanConfluent]

Describe the bug
We have an error message:

A known bug is found while restoring the command topic. The restoring
process will continue, but the query of the affected stream or table won't 
be executed until https://github.com/confluentinc/ksql/issues/8173 is fixed.

Now #8173 is fixed, so we should remove the message.

To Reproduce
Steps to reproduce the behavior, include:

1. The version of KSQL.
2. Sample source data.
3. Any SQL statements you ran

Expected behavior
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Actual behaviour
A clear and concise description of what actually happens, including:

1. CLI output
2. Error messages
3. KSQL logs

Additional context
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