Upgrading @rest-hooks/test to 7

Importing directly from hidden files is no longer supported

All packages now use package exports, which if supported disallow importing directly from any sub path like rest-hooks/lib/MockResolver

Doing this was never supported as file locations would change without announcement. However, now with tooling that supports package exports, it will not work at all.

Node >= 12

Node 10 support is dropped.

@rest-hooks/test@7 Release notes