Draft: Add option to suppress repeated error log messages

[robinnewhouse]

I am seeking feedback on this solution before going any further with it. I would like to limit the rate of error log messages that is different than fully suppressing them like mysql's log_error_suppression_list or configuring the verbosity level

Description

Add a new configuration option log_suppress_repeated_errors that allows users to control the behavior of error logging. When this option is set to a non-zero value, the server will suppress repeated identical error messages after the specified number of occurrences.

This is implemented by tracking the last logged error message and its count. If a new message matches the previous one, and the count has not reached the suppression limit, the message is not logged again. Once a new unique message is encountered, the previous message's count is logged, and the new message is printed.

The suppression can be disabled by setting the option to 0.

Default behaviour (log_suppress_repeated_errors = 0).

2024-10-04 22:13:01 5 [Warning] Access denied for user 'foo'@'localhost' (using password: YES)
2024-10-04 22:13:04 6 [Warning] Access denied for user 'foo'@'localhost' (using password: YES)
2024-10-04 22:13:05 7 [Warning] Access denied for user 'foo'@'localhost' (using password: YES)
2024-10-04 22:13:06 8 [Warning] Access denied for user 'foo'@'localhost' (using password: YES)
2024-10-04 22:13:22 9 [Warning] Access denied for user 'bar'@'localhost' (using password: YES)```

Suppressing errors after 3 identical repetitions.

MariaDB [(none)]> SET GLOBAL log_suppress_repeated_errors = 3;

2024-10-04 22:14:06 12 [Warning] Access denied for user 'foo'@'localhost' (using password: YES) 2024-10-04 22:14:09 13 [Warning] Access denied for user 'foo'@'localhost' (using password: YES) 2024-10-04 22:14:13 14 [Warning] Access denied for user 'foo'@'localhost' (using password: YES) 2024-10-04 22:14:29 19 [Warning] The following message was emitted 7 times (repeated instances suppressed): Access denied for user 'foo'@'localhost' (using password: YES) 2024-10-04 22:14:29 19 [Warning] Access denied for user 'bar'@'localhost' (using password: YES)

## Release Notes
[WIP]

## How can this PR be tested?

[WIP: writing MTR tests]

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