feat: allow searching articles in omnisearch (#11558)

Co-authored-by: Sivin Varghese <64252451+iamsivin@users.noreply.github.com>

app/views/api/v1/accounts/search/articles.json.jbuilder

@@ -0,0 +1,7 @@
+json.payload do
+  json.articles do
+    json.array! @result[:articles] do |article|
+      json.partial! 'article', formats: [:json], article: article
+    end
+  end
+end