Run and update conformance dumps in github action

[Snafuh]

This adds an action to build all libraries, run the bench suite and update the dump files.

A few considerations:

• The dump files are changed/committed every run, as some temporary file names are changing each run. To make it easier to diff and compare two file versions, the format of the output JSON had to be adjusted
• This doesn't update the submodules. This had to be done manually. An action would still help, as it's reliable and easy to trigger. But a weekly cron doesn't make much sense without submodule commit updates.
• The website does not update. The other action had to be triggered to publish it with new files.

Happy any feedback on this :)

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