Add docs for bearer_auth helper

Author: robsdedude

docs/source/api.rst

@@ -116,7 +116,7 @@ Example:
 
     import neo4j
 
-    auth = neo4j.Auth(scheme="basic", principal="neo4j", credentials="password")
+    auth = neo4j.Auth("basic", "neo4j", "password")
 
 
 Auth Token Helper Functions
@@ -128,6 +128,8 @@ Alternatively, one of the auth token helper functions can be used.
 
 .. autofunction:: neo4j.kerberos_auth
 
+.. autofunction:: neo4j.bearer_auth
+
 .. autofunction:: neo4j.custom_auth