Fix setting fullname for ORCID

Originally, fullname was set to `response['person']['name']`, which in
ORCID is a large json object. Everywhere else, fullname is assumed to be
a string. It cannot be used directly as a fullname but needs converting.

social_core/backends/orcid.py

@@ -70,11 +70,11 @@ def get_user_details(self, response):
         if person:
             name = person.get('name')
 
-            fullname = name
-
             if name:
                 first_name = name.get('given-names', {}).get('value', '')
                 last_name = name.get('family-name', {}).get('value', '')
+                fullname = first_name + ' ' + last_name
+                fullname = fullname.strip()
 
             emails = person.get('emails')
             if emails: