Allow more than match queries in custom filters

If a user attempted to create a custom filter without a match query
Kibana would error out because it assumed all queries were match
queries. This adds a stricter conditional so that we only attempt to
read the match config if a match property actually exists.

src/ui/public/filter_manager/filter_manager.js

@@ -23,7 +23,7 @@ export default function (Private) {
           return filter.exists.field === value;
         }
 
-        if (filter.query) {
+        if (_.get(filter, 'query.match')) {
           return filter.query.match[fieldName] && filter.query.match[fieldName].query === value;
         }