Add in Atomfeeds deprecation now that the extension has a new release…

[seamuslee001]

… with converted cache mechanism

Overview

Now that the Atomfeeds extension has a new release https://github.com/Chirojeugd-Vlaanderen/atomfeeds/releases/tag/0.1-alpha3 which incorporates a cache conversion we should implement the same deprecation here as with multisite and entity setting

Before

No deprecation

After

Deprecation as newer version of extension correctly uses newer cache mechanism

ping @eileenmcnaughton

[civibot]

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[eileenmcnaughton]

@seamuslee001 at the moment you still have to add a define to civicrm.settings.php to opt into this?

[seamuslee001]

@eileenmcnaughton yes but also the more that use the Civi::cache then are doing things PSR16 format

[eileenmcnaughton]

@seamuslee001 OK -yes I agree this is good to do - I just want to understand the steps to get switched over & I think maybe the first is to ensure we have some live testing of the define followed by making it the default on new installs

[seamuslee001]

Test fail unrelated