[WIP] Clean up dev dependencies + bump versions

[kirrg001]

refs 75234
refs 80052

See advantages:
https://github.com/lerna/lerna#common-devdependencies

• common dependencies to root
• version updates
• removal of unused dependencies
• package-lock not updated when only using local packages lerna/lerna#3029
• Can devDependencies in the root package.json be used in all repos without installing in each individually? lerna/lerna#1079 (not sure about mocha being in root because it's CLI dependency?)
• --legacy-peer-deps required, because of NPM bug (usually only happens when you move deps to root)

---

before:
real 6m47.953s
user 5m49.277s
sys 3m34.443s

after:

[kirrg001]

Also closing this PR after thinking about it another time.

lerna/lerna#3029 is in our way. It is impossible to move common dependencies to the root if we always have to take care that lerna does not mess up our lock file.

On top of that we are running into npm/cli#4084. It forces us to use legacy peer deps option, which we don't want, because this will install a wrong dependency tree. This might lead to wrong assumptions in our test env.

I think we should only do a few smaller clean up steps and then leave it as it is:

• ensure major versions (such as mocha, semver etc) of dev dependencies are equal
• general update of dev dependencies
• add some lerna dependency docs (how to use it - some workflows should be documented IMO)
• removal of unused dependencies
• research if there is more

[kirrg001]

Conclusion:

• we have the option to add rules how to use lerna with common dev dependencies on root
• we look at it with a pair of new eyes (in a new PR)