Implement design changes for election search, data landing and homepage to add missing feature message

[JonellaCulmer]

What we're after:
Update the election search, data landings and homepage to remove the map, disable the zip code filter and add new message explaining changes.

Related tickets:

• Begin new A/B test for data landing page #5088
• Design election search page updates for outdated district boundary map #5210
• Update district dropdown to reflect changes #5204

Designs:

• Design election search page updates for outdated district boundary map #5210 (comment)

Action items:

• Remove map
• Remove accordion (should remain gone after reverting all other changes and the map is replaced)
• Disable zip code filter
• Add label under zip code filter:
  "Temporarily unavailable" size 14/1.4rem, italic
• Add new message:
  "The election map and zip code search are unavailable at this time. Following the 2020 Census, some states may redraw their districts. Some candidates may subsequently amend their registration forms to reflect new district numbers. Candidates are listed using information from their registration forms and may run in different districts than in the past. The FEC will reenable the map and zip code search once complete information has been made available from each state."
• Put under a feature flag to revert these changes when we have the maps ready to go

Completion criteria:

• Election search, data landing pages and homepage are updated

[rfultz]

Moving this to the ice box since it's been a while

[JonellaCulmer]

No longer needed since the new maps are up.