release-20.2: ui: Redesign custom date range component

Lauren Singh (lnhsingh) commented:

PR: https://github.com/cockroachdb/cockroach/pull/57115

From release notes:
> Updated design for custom date range selector on the [Cluster > Node Map](../v20.2/ui-cluster-overview-page.html#node-map-enterprise) and [Metrics](../v20.2/ui-overview-dashboard.html] pages. [#57115][#57115) {% comment %}doc{% endcomment %}

Jira Issue: DOC-882