Add actor for mysql migration RHEL9->RHEL10

[SlouchyButton]

Basic actor that just checks that the mysql-server package is installed and inform user if so.

There are incompatibilities, so there is an article attached describing the process (the article is WIP)

[github-actions]

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[SlouchyButton]

/packit copr-build

[SlouchyButton]

Added configuration checks, so the user is informed that current MySQL configuration won't be compatible with newer MySQL present in RHEL 10.

When incompatible config is detected, severity is also raised to HIGH, as proceeding will result in mysqld failing to launch until issues with config are resolved.

[pirat89]

@SlouchyButton hi \o thanks for the contribution! regarding the severity, if I understand it right, the worst scenario here is that mysqldb will not be launched on the new system - will not be working - until they fix the configuration. fro mthis point I do not think we should use high severity.

• High - Very likely to result in a deteriorated system state.
• Medium - Can impact both the system and applications.
• Low - Should not impact the system but can have an impact on applications.
• Info - Informational with no expected impact to the system or applications.