SDR has extraneous "suggest" route

[spilth]

The routes file has a resources route for suggest but:

• There's only 1 request to this URL in production in the last week and I’m pretty sure that was me testing it
• It doesn’t seem to be used anywhere in the codebase
  • Note that Solr’s /suggest is something different
• It maps to a Rails controller that does not exist
• It currently returns {"status":404,"error":"Not Found"}
• The test suite still passes when this route is removed

I suspect this was some pre GBL 4 route that can be safely removed.

[spilth]

Fixed by #358