[FFe] Sync prometheus-mysqlrouter-exporter as new package from Debian unstable

[Lena Voytek]

Dear Release Team,

Please accept prometheus-mysqlrouter-exporter as a new universe package, synced from Debian.

[Rationale]

prometheus-mysqlrouter-exporter provides users with the ability to include MySQL data and statistics to their prometheus environment via the mysql router. Likewise, the data platforms team includes this package in projects such as charmed MySQL, and having the package in noble would make the process more convenient.

[Regression Potential]

The package has no reverse-dependencies, will not be seeded, and will not affect users who do not install it. So the potential for regression would be limited to problems due to installing the package on an existing system.

[Tests]

The package includes 2 autopkgtests to verify runtime functionality. The first confirms that the mysqlrouter_exporter command exists. The second verifies that mysqlrouter_exporter can connect to and extract data from a standard MySQL router instance with a provided configuration.