fix: [DPE-6234] Disable general_log and plugin audit_log_filter (#574)

* fix: [DPE-6234] Disable general_log and plugin audit_log_filter

The config option general_log is not compatible with the real
productions due to dumping all SQL queries to the general.log:
https://dev.mysql.com/doc/refman/8.0/en/query-log.html

> ... The server writes information to this log when clients connect or
> disconnect, and it logs each SQL statement received from clients...

In the past, it was a necessary evil as we had to keep record all
connects/disconnects from the clients for security reasons.
Nowadays we have audit_log plugin enabled by default, therefor no need to
pay such a high performance price and struggle from the general.log size

#523 (comment)
>  33GB /var/snap/charmed-mysql/common/var/log/mysql/archive_general/general.log-20241212_0013

Additionally, we are working on the logs compression spec (separate topic).

---

While working here, we have noticed unnecessary enabled plugin audit_log_filter
which also produces log files in /var/lib/mysql. Disabling it for now,
as it is not necessary for audit_log plugin announcer functionality.

We will consider re-enabling the plugin without rush in
https://warthogs.atlassian.net/browse/DPE-6235

* Fix unit tests

* Add loose- prefix for audit_log_filter to start MySQL

Otherwise MySQL didn't start as the option is unknown until plugin is loaded.

* Remove general.log from tests

* finishing general log removal

* update cffi as 1.16 has no binary for py3.13

* further test fixes and typing update

---------

Co-authored-by: Alex Lutay <[email protected]>

Author: paulomach

lib/charms/mysql/v0/mysql.py

@@ -133,7 +133,7 @@ def wait_until_mysql_connection(self) -> None:
 # Increment this major API version when introducing breaking changes
 LIBAPI = 0
 
-LIBPATCH = 78
+LIBPATCH = 79
 
 UNIT_TEARDOWN_LOCKNAME = "unit-teardown"
 UNIT_ADD_LOCKNAME = "unit-add"
@@ -1002,10 +1002,11 @@ def render_mysqld_configuration(  # noqa: C901
             "innodb_buffer_pool_size": str(innodb_buffer_pool_size),
             "log_error_services": "log_filter_internal;log_sink_internal",
             "log_error": f"{snap_common}/var/log/mysql/error.log",
-            "general_log": "ON",
+            "general_log": "OFF",
             "general_log_file": f"{snap_common}/var/log/mysql/general.log",
             "slow_query_log_file": f"{snap_common}/var/log/mysql/slow.log",
             "binlog_expire_logs_seconds": f"{binlog_retention_seconds}",
+            "loose-audit_log_filter": "OFF",
             "loose-audit_log_policy": "LOGINS",
             "loose-audit_log_file": f"{snap_common}/var/log/mysql/audit.log",
         }