[FIX] base: do not crash on gravatar timeout

ConnectionError is raised when there is no internet connection
if case of timeout a ConnectTimeout or ReadTimeout is raised.
It was not catched.

requests.exceptions.Timeout catches both

odoo/addons/base/res/res_partner.py

@@ -709,6 +709,8 @@ class Partner(models.Model):
                 return False
         except requests.exceptions.ConnectionError as e:
             return False
+        except requests.exceptions.Timeout as e:
+            return False
         return base64.b64encode(res.content)
 
     @api.multi