Taxonomy: Restore (un-deprecate) the `tag_row_actions` filter.

The filter provides a simple way for plugin authors to add actions generically for all taxonomy list tables without looping through each taxonomy individually.

Props joemcgill, delowardev.
Fixes #49808.
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git-svn-id: https://core.svn.wordpress.org/trunk@47510 1a063a9b-81f0-0310-95a4-ce76da25c4cd