Add missing dependencies for release tooling

[weirdwater]

A few dependencies slipped through the cracks when migrating to pnpm: #132

[weirdwater]

The issue with the PWT command tests turned out to be that the node setup action would attempt to cache the pnpm-store. But since the pnpm install command was behind an if-condition the store would not fill up. Reviewing the conditional steps it became clear that the workflow did not do anything if the path filters were not met.

Since there was also no difference in behavior based on the "packages" and "tests" filters I decided to move these conditions to the workflow level, simplifying the script.

Armed with the knowledge that with pnpm there really is no point in caching the node_modules directory and that the node-setup action already caches the pnpm store I removed the existing caching strategy.

I have also applied these lessons to the unit test workflow.