=== Background
This is a companion task to {T386659}.
Previously, instrument and experiment configs were fetched from xLab and cached synchronously. We chose a short cache lifetime so that the configs were always fresh. However, synchronously fetching configs from xLab is expensive if the application servers are not in eqiad, where xLab is currently deployed, and so we made updating the configs asynchronous in {T398422}.
Since the configs are not guaranteed to be fresh, there is a chance that a config for a now-inactive experiment could be fetched from the backing store. Therefore, MetricsPlatform needs to be updated to filter inactive configs.
=== AC
[v] Add dates to xLab output so MW can see them ([[https://gitlab.wikimedia.org/repos/data-engineering/mpic/-/merge_requests/224|merged]] and deployed on production)
[] MW MetricsPlatform extension checks that current day falls between start and end dates of the experiment ([[https://gerrit.wikimedia.org/r/1177961|merged]])
** This should only be done once the change for (1) has been deployed
[] xLab includes also future experiments in the API response when mediawiki is the authority (`/api/v1/experiments?format=config&authority=mediawiki`)
=== Deployment plan
https://phabricator.wikimedia.org/T399292#11106159