Fix lockfile, fix .yarnrc.yml setting

[krassowski]

Relates to #43

Description

This pull request:

• fixes lock file which was mistakenly generated with a wrong version of yarn/jlpm
• removes enableImmutableInstalls it should not be set to false for security reasons; it should not be set to true for annoyance reasons; the default: true on CI, false locally is best IMO.

Pull request checklist

• Did you test this change locally?
• Did you update the documentation (if required)?
• Did you add/update relevant tests for this change (if required)?

Additional information

None

How to test

CI shouuld pass

[trallard]

I was going to say it was odd because I had just updated the dependencies 🤔
thank you