Drop (now meaningless) JSON data message check from pgcon.pyx
Fixes
@@ -318,12 +318,6 @@ cdef class PGProto:
f'received NULL for a JSON query {sql!r}')
self.buffer.discard_message()
continue
- if coll <= 2:
- error = RuntimeError(
- f'unable to unpack DataRow '
- f'for a JSON query {sql!r}')
- self.buffer.discard_message()
- continue
data = self.buffer.read_bytes(coll)
