Update default.nix

[freesig]

PR summary

Just testing the --tap option to see if we can get output for the stuck test.

testing/benchmarking notes

( if any manual testing or benchmarking was/should be done, add notes and/or screenshots here )

followups

( any new tickets/concerns that were discovered or created during this work but aren't in scope for review here )

changelog

• if this is a code change that effects some consumer (e.g. zome developers) of holochain core, then it has been added to our between-release changelog with the format

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

documentation

• this code has been documented according to our docs checklist

[thedavidmeister]

@freesig did it work?

[freesig]

It does work but I'm not sure if you want it in the regular testing as it creates a lot of noise

[zippy]

@freesig is this still relevant or should we close?