Add language parser fuzzer

[AdamKorcz]

This PR adds a fuzzer for the language parser API.

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Patch Set 1: Run-TryBot+1 Code-Review+2 Trust+1

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Patch Set 1: TryBot-Result+1

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Message from Heschi Kreinick:

Patch Set 1: Trust+1

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Message from Marcel van Lohuizen:

Patch Set 1: Run-TryBot+1 Code-Review+2 Trust+1

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Message from Go Bot:

Patch Set 1: TryBot-Result+1

(1 comment)

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[gopherbot]

Message from Heschi Kreinick:

Patch Set 1: Trust+1

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After addressing review feedback, remember to publish your drafts!