test: store nocks in a sqlite database

[merceyz]

Storing the nocks in a SQLite database enables easily sharing nocks between tests run in different processes in parallel.

This reduces the storage space needed for the nocks:

$ du tests/nock
- 186700  tests/nock
+  48968  tests/nock

It avoids the v8.serialize / v8.deserialize issues encountered in #365.

The database is portable so the version of Node.js used to generate it doesn't matter.

[aduh95]

I wonder if this approach will not introduce a conflict-hell, if virtually all PRs will touch the same binary file.

[merceyz]

I wonder if this approach will not introduce a conflict-hell, if virtually all PRs will touch the same binary file.

Yeah, that's the downside of this approach, any new nock will cause a conflict.
However since nocks can be re-used between tests it's possible the nock is already in the database.
If it becomes too much we can always add some automation to handle it.

[arcanis]

That seems a good idea; slightly worried about the risk of conflicts too (especially if it breaks the "Update this PR" button in GH), but it's probably fine to try it and iterate as needed.