feat: LogArgsSerializer to customize how args are converter to string

[mxab]

Why

The default behaviour in pushLogs stringifies all arguments in a very simple way. This results in potential [object Object] log messages if some one or some third party library decides to put complex logs arguments e.g. console.info({foo: "bar"})

What

This PR extends the faro config with a logArgsSerializer paremeter that allows to override the default behaviour and put in a custom args renderer

fixes #564

Checklist

• [x] Tests added
• [x] Changelog updated
• [x] Documentation updated

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[codecapitano]

Hi @mxab can you also add the new property to the core readme please.

Section: Besides the mandatory properties, Faro configuration also supports the following optional properties:

[mxab]

Done, do you want me to squash the changes?

[codecapitano]

Done, do you want me to squash the changes?

Hey Max you don't need to squash them yourself. We'll squash & merge them via GH.

[mxab]

yeah I only executed the linter in the core package. thx

[mxab]

at last the linter approves 😅