MSC3966: `event_property_contains` push rule condition (#3966)
* Add proposal for exact_event_property_contains push condition.
* Fix incorrect word.
Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>
* Fix broken link.
* Fix typo.
Co-authored-by: Hubert Chathi <hubertc@matrix.org>
* Update condition name.
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Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>
Co-authored-by: Hubert Chathi <hubertc@matrix.org>