deprecate_disable: beginning to phase out Quick Look plugins

[Mick235711]

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Old-style Quick Look plugins (those with a .qlgenerator extension) were deprecated since Catalina, and Apple decided to remove support for them last year since Sequoia. This means that the 38 casks with qlplugin artifacts will no longer work on Sequoia and newer systems. Given that Sonoma support will likely be dropped from the CI next year, this means that shortly after macOS 27's release, these casks will no longer work on any Tier 1 configuration.

Most of the casks mentioned are not updated for several years at this point. Newer QL plugins will utilize the Quick Look Thumbnailing Extension and appear directly as a normal .app, for example QLVideo.

Therefore, this PR tries to add a reason in preparation for their deprecation.

[p-linnane]

Thanks for the PR. I agree we should deprecate these, but I don't think we should add a new reason for a one-off. @Mick235711 Can you open a PR to deprecate these, but use the no_longer_meets_criteria? Thanks!

[bevanjkay]

I hadn't had a chance to get to this yet, but I had the same thought as @p-linnane.
It would be good to update the documentation to either remove the references to the qlplugin artifact, or note that they are now deprecated.

[Mick235711]

Thanks for the PR. I agree we should deprecate these, but I don't think we should add a new reason for a one-off. @Mick235711 Can you open a PR to deprecate these, but use the no_longer_meets_criteria? Thanks!

Sure, done.

It would be good to update the documentation to either remove the references to the qlplugin artifact, or note that they are now deprecated.

Sure, I opened another PR (#20744) to try to achieve that.