default value is out of synch between the nextflow.config and nextflow_schema.json

[jenmuell]

Description of the bug

During the hackathon I was working on an issue for the parameter schema and was checking which parameters I can change in the graphical interface. Thereby I changed the default value of a parameter and recognized that the corresponding parameter in the nextflow.config was not updated.
Connected to Issue and PR

A possible solution would be to highlight this behaviour with a tooltip, to inform the user that he has to update the nextflow.config file or to disable a change of the default value.

[ewels]

Would be good to lint for this, but allow for the .nf-core.yml file to ignore specific parameters where this may be desired (eg. complex deferred param defaults in the config and a simple string in JSON).

[mirpedrol]

Added the linting test with #2684