Remove `roadmap_daterange_filter` feature flag and related legacy code from Roadmap app

Merged Kushal Pandya requested to merge 323917-remove-roadmap_daterange_filter-ff into master

What does this MR do and why?

This MR removes roadmap_daterange_filter feature flag and related code from Roadmap app.

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Related to #323917 (closed)

Edited by Kushal Pandya