pgsql: Clean up misuse and nonuse of poll_query_until().

Clean up misuse and nonuse of poll_query_until().

Several callers of PostgresNode::poll_query_until() neglected to check
for failure; I do not think that's optional. Also, rewrite one place
that had reinvented poll_query_until() for no very good reason.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b0f069d931f0a3d4a39aeeb230baf2f2b18cb3c3

Modified Files
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src/test/modules/commit_ts/t/003_standby_2.pl | 3 ++-
src/test/perl/PostgresNode.pm | 2 +-
src/test/recovery/t/001_stream_rep.pl | 3 ++-
src/test/recovery/t/005_replay_delay.pl | 20 +++-----------------
src/test/recovery/t/006_logical_decoding.pl | 9 ++++++---
.../recovery/t/010_logical_decoding_timelines.pl | 7 +++++--
6 files changed, 19 insertions(+), 25 deletions(-)