Responsive View - replace categories filter with matching pool filter on the grants explorer

As a grants app user, I want a clear understanding of the nomenclature hierarchy of a round, and not be confused with legacy elements so it is consistent and clear when I am filtering on grants.

This task is a follow up build responsive views.

**Acceptance Criteria**
GIVEN I am viewing the grants explorer on mobile during an active grants round
WHEN I tap the grant round filter
THEN I should see a dropdown menu open showing each CLR type with a carat symbol pointing up for an open menu, and down for a closed menu

GIVEN I am viewing the grant round filter on the grants explorer
WHEN I tap a CLR type
THEN I should see a secondary menu open showing each CLR I can filter by
AND The down carat symbol should point up
AND Open menus should close

GIVEN I am viewing the grants explorer on desktop during an active grants round
WHEN I tap the grant round filter
THEN The carat symbol should not appear

[design link](https://www.figma.com/file/wZtLnSb0mLPVnj8f4BkfVX/Grants-2021?node-id=701%3A11196)
[Jira Link](https://gitcoin.atlassian.net/browse/GITC-633?atlOrigin=eyJpIjoiYjg2NzczNzNkMTY2NDdmNTg5YTVjNWFiZjY2Yzc2NWQiLCJwIjoiaiJ9)