kt-paperclip version mismatch

[tvdeyen]

kt-paperclip is open ended in v2.11.5 but constrained to v6 in latest versions.
This allows paperclip v7 in 2.11.15 and only v6 in 3.0 and above. Not sure if this intentional
or a mistake. It surely is confusing for folks updating from v2 to v3

Solidus Version:

>= v2.11.15

To Reproduce

See the core gemspec in master https://github.com/solidusio/solidus/blob/master/core/solidus_core.gemspec#L44
The gemspec in v2.11.15 https://github.com/solidusio/solidus/blob/v2.11/core/solidus_core.gemspec#L42

Not sure what is the expected version. Happy to provide a PR if we agree on a version we want to support.

[spaghetticode]

Definitely not intentional (I introduced KT-Paperclip on v2.11), I agree we should have the same high version constraint that we have in 3.x

[kennyadsl]

@tvdeyen do you think we can close this one now? BTW, I saw that master now allows kt-paperclip 7 as well.

[tvdeyen]

Yes