Ensure that boolean params in the API are parsed for truthiness (#6575)

Use Rails smart boolean cast to account for values such as "f",
"0", "false", etc. Previously, if a param was present in the request,
it would count as true.

app/controllers/api/v1/search_controller.rb

@@ -33,12 +33,8 @@ class Api::V1::SearchController < Api::BaseController
     SearchService.new.call(
       params[:q],
       RESULTS_LIMIT,
-      resolving_search?,
+      truthy_param?(:resolve),
       current_account
     )
   end
-
-  def resolving_search?
-    params[:resolve] == 'true'
-  end
 end