Removed plaintext formats from posts request

refs https://github.com/TryGhost/Team/issues/1665
refs https://github.com/TryGhost/Ghost/issues/10396

- Content API has been updated to return clean results for `excerpt` without require a hacky "&formats=plaintext" parameter

ghost/sodo-search/src/search-index.js

@@ -57,8 +57,7 @@ export default class SearchIndex {
         let posts = await this.api.posts.browse({
             limit: 'all',
             fields: 'id,slug,title,excerpt,url,updated_at,visibility',
-            order: 'updated_at DESC',
-            formats: 'plaintext'
+            order: 'updated_at DESC'
         });
 
         if (posts || posts.length > 0) {