Set clause with invalid syntax causes abnormal termination

[pdpotter]

Describe the bug
When using a set clause with an invalid syntax, the server is terminated abnormally and the connection is closed.

How are you accessing AGE (Command line, driver, etc.)?

• psql

What data setup do we need to do?

...
SELECT * FROM cypher('test_graph', $$CREATE (p:person {id: 1, name: 'Jane'}) return p$$) as (p agtype);
                                              p                                              
---------------------------------------------------------------------------------------------
 {"id": 844424930132088, "label": "person", "properties": {"id": 1, "name": "Jane"}}::vertex
(1 row)
...

What is the necessary configuration info needed?
/

What is the command that caused the error?

SELECT * FROM cypher('test_graph', $$Match (p:person {id: 1}) set name = "Janine"  return p$$) as (p agtype);

server closed the connection unexpectedly
	This probably means the server terminated abnormally
	before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.

Expected behavior

• A syntax error message like

ERROR:  syntax error at or near "n"
LINE 1: ...from cypher('test_graph', $$Match (p:person {id: 1}) set name = "Janine"  return p...
- no server termination

Environment (please complete the following information):

• Version: bf9d836

Additional context

• The correct syntax is

SELECT * FROM cypher('test_graph', $$Match (p:person {id: 1}) set p.name = "Janine"  return p$$) as (p agtype);

• This causes indexes to be corrupted as well.