Reapply "Use both og and oembed title"

This reverts commit ad618ba.

plugins/domains/documentcloud.org.js

@@ -9,7 +9,8 @@ export default {
         "author",
         "og-title",
         "og-image",
-        "og-description"
+        "og-description",
+        "oembed-title"
     ],
 
     // plugin is required to add aspect-ratio and with this fix embeds when used inside iFrame
@@ -100,7 +101,8 @@ export default {
             'author',
             'canonical',
             'og-title',
-            'og-image'
+            'og-image',
+            'oembed-title'
         ]},
         'https://www.documentcloud.org/documents/73991-day-three-documents',
         'https://www.documentcloud.org/documents/5766398-ASRS-Reports-for-737-max8.html#document/p2/a486265',