AO3-6576 Published date in news post blurb is unnecessarily complex to screen readers

[forceofcalm]

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Issue

https://otwarchive.atlassian.net/browse/AO3-6576

Purpose

This removes the extraneous <span>s wrapped around the date/time elements on news posts, work blurbs, and anything else that uses date_in_zone to improve screenreader accessibility. A comment on the Jira ticket also noted that the time zone's title seemed strange, so it has been updated to use the unabbreviated time zone name instead of the Country/City it previously used.

Credit

calm (they/them)