Improve some psql test code
Split psql_like() into two functions psql_like() and psql_fails_like()
and make them mirror the existing command_like() and
command_fails_like() more closely. In particular, follow the
universal convention that the test name is the last argument.
Discussion: https://www.postgresql.org/message-id/
3199e176-424e-1bef-f180-
c1548466c2da@enterprisedb.com