Try to create a version record when associated object is touched

[y-yagi]

Before #1285, a version record was created when associated object is touched.
But because of Rails don't track implicit touch mutation1, now PaperTail don't create a version record was created when associated object is touched.

This patch try to keep creating a version record in that case by doing checking an event and changed value.

Fixes #1339.

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[jaredbeck]

LGTM. WDYT @westonganger @quainjn @tlynam ?

[westonganger]

Sure looks good I guess, not sure I should be considered an expert here though.

[jaredbeck]

Thanks @y-yagi !

[y-yagi]

Thanks for your review!

[KevinBongart]

Thank @y-yagi for the patch! I noticed the same issue, identified the root cause and found this PR before I attempted to fix it :D

@jaredbeck Any ETA for when this patch will make its way into a new release?

[steve21168]

I'm actually looking to do the opposite of this. I don't want a version record when the association is touched. In my case it's creating extraneous version records showing no object changes.

To fix this, I added has_paper_trail ignore: [:updated_at]. However this change doesn't take into account ignore or skip. So now when associated objects are touched there's no way to avoid these version records.

Any ideas to work around this?