pgsql: Add error pattern checks for some TAP tests for non-existing obj

Add error pattern checks for some TAP tests for non-existing objects

Some tests are updated to use command_fails_like(), gaining a check for
the error output generated. The test changed in pg_amcheck has come up
after noticing that an incorrect option name still made the test to
pass, while the command failed. The three other tests changed in
src/bin/scripts/ have been noticed by me, in passing.

Author: Dagfinn Ilmari Mannsåker, Michael Paquier
Discussion: https://postgr.es/m/87bjvy50cs.fsf@wibble.ilmari.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/eef4a33f62f7300765b5ffa8c966fa2fba50d176

Modified Files
--------------
src/bin/pg_amcheck/t/002_nonesuch.pl | 5 ++++-
src/bin/scripts/t/010_clusterdb.pl | 4 +++-
src/bin/scripts/t/050_dropdb.pl | 4 +++-
src/bin/scripts/t/070_dropuser.pl | 4 +++-
4 files changed, 13 insertions(+), 4 deletions(-)