Add compatibility with monolog v3

[W0rma]

Fixes #1318

[W0rma]

I'm a bit unsure on how to fix the phpstan and psalm pipeline.

psalm seems to analyse the code based on PHP 7.2 and I don't know how to change that.

The phpstan errors are related to the BC layer which makes sure that the handler can be used in monolog v2 and v3. Should I add the reported "errors" to the baseline file?

[ste93cry]

Thank you for the contribution. Since this is not a bug fix, please target the develop branch.

psalm seems to analyse the code based on PHP 7.2 and I don't know how to change that.

Technically speaking, it's correct that Psalm complains because the code should run on any PHP version down to 7.2. I think that the only viable solution is to update the baseline and ignore the errors. A more appropriate way could be to run the analysis more than once, one for PHP 7.2 and one for PHP 8.0 though, but it would be a bigger change and I wouldn't tackle it here

The phpstan errors are related to the BC layer which makes sure that the handler can be used in monolog v2 and v3. Should I add the reported "errors" to the baseline file?

The error is because PHPStan does not understand that the Logger::API constant can change depending on which version of the package is installed. It should be enough to instruct it that the constant is dynamic by using the dynamicConstantNames option.

[W0rma]

@ste93cry Thank you for the hints! I have changed the target branch to develop and addressed all your suggestions.

[Jean85]

Good work! Please add a changelog entry.

[W0rma]

Please add a changelog entry.

@Jean85 Done

[ste93cry]

I've left a few more comments, but they are just nitpick. You should also rebase the PR to solve the issues with PHPStan errors. The only concern I have, but to which I don't think there is solution that can be easily taken here, is that it looks weird to see errors related to the vendor folder in the Psalm baseline 😞

[ste93cry]

Thank you for the hard work!