Adds "bypass" feature to locksmith

[maackle]

PR summary

When using features = ["bypass"] for locksmith cargo dep, replaces all locksmith mutex and guard types with a minimal wrapper exposing the same API but that actually does nothing. We should probably use this in production, unless it turns out to be almost as fast to optimize the real locksmith functionality, especially by disabling backtraces in favor of source_loc.

testing/benchmarking notes

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followups

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changelog

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- summary of change [PR#1234](https://github.com/holochain/holochain-rust/pull/1234)

documentation

• this code has been documented according to our docs checklist

[neonphog]

👍

[freesig]

🆗