Latest semver-matching dependencies fail unit tests

[Conduitry]

If you currently install dependencies with npm install, many (all?) of the unit tests fail with ReferenceError: __makeTemplateObject is not defined. Installing with Yarn is fine, as that always gives the same versions for every package.

This is inconvenient for contributors, but also currently makes CI jobs fail. We should probably figure out what happened recently with npm packages. Probably we should also make the CI jobs install using Yarn instead of npm, even though that would make situations like this possibly harder to spot right away.