fix(logs): Allow passing string and enum Monolog level

[HypeMC]

Description

Currently, the constructor only accepts integers as the log level, e.g. by using the Monolog\Logger constants:

services:
  Sentry\SentryBundle\Monolog\LogsHandler:
    arguments:
      - !php/const Monolog\Logger::INFO

This, however, isn't very flexible, especially since the Monolog constants are deprecated.
This PR expands the accepted types to also allow strings or the Monolog Level enum, like other handlers:

services:
  Sentry\SentryBundle\Monolog\LogsHandler:
    arguments:
      - 'info'

# or using PSR constants
services:
  Sentry\SentryBundle\Monolog\LogsHandler:
    arguments:
      - !php/const Psr\Log\LogLevel::INFO

// or via PHP config
$container->services()
    ->set(\Sentry\SentryBundle\Monolog\LogsHandler::class)
    ->args([\Monolog\Level::Info]);

[HypeMC]

Seems to be a bug in Psalm when using const on enums: https://psalm.dev/r/a6f9298b82

[Litarnus]

Thanks for your contribution, it makes a lot of sense to allow string levels!

[Litarnus]

This will throw if an invalid level is passed. Please default to Info in such a case like getSentryLogLevelFromMonologLevel does. Also this would benefit from a test case.

[HypeMC]

@Litarnus Done, de332aa

[Litarnus]

Nice, thank you!