[jdks] Add offline mode

[charphi]

Is your feature request related to a problem? Please describe.
jdks:setup-disco fails when offline which is normal since it calls a webservice.
The problem is that this behavior stops my entire workflow even if the JDK is already in the cache.

Describe the solution you'd like
Don't fail when offline if everything is already in the cache.
Could be done by putting the response of disco API in the cache alongside the JDK.

Describe alternatives you've considered
My current workaround is to copy-paste manually the jdk in the right folder and then launch my workflow using the disco.setup.skip parameter.

Additional context
My corporate Windows laptop is not really offline but some operations are restricted when on site (works fine out of office).