pgsql: Introduce PG_TEST_TIMEOUT_DEFAULT for TAP suite non-elapsing tim

Introduce PG_TEST_TIMEOUT_DEFAULT for TAP suite non-elapsing timeouts.

Slow hosts may avoid load-induced, spurious failures by setting
environment variable PG_TEST_TIMEOUT_DEFAULT to some number of seconds
greater than 180.  Developers may see faster failures by setting that
environment variable to some lesser number of seconds.  In tests, write
$PostgreSQL::Test::Utils::timeout_default wherever the convention has
been to write 180.  This change raises the default for some briefer
timeouts.  Back-patch to v10 (all supported versions).

Discussion: https://postgr.es/m/20220218052842.GA3627003@rfd.leadboat.com

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/29ec94efd08b0b3f863db13f5978cdeab4f1c8dc

Modified Files
--------------
contrib/amcheck/t/002_cic.pl                       |  3 ++-
contrib/amcheck/t/003_cic_2pc.pl                   | 14 +++++++------
src/bin/pg_ctl/t/004_logrotate.pl                  |  2 +-
src/bin/pg_dump/t/002_pg_dump.pl                   |  3 ++-
src/bin/psql/t/010_tab_completion.pl               |  6 +++---
src/bin/scripts/t/080_pg_isready.pl                |  4 ++--
src/test/perl/PostgresNode.pm                      | 24 +++++++++++++---------
src/test/perl/TestLib.pm                           |  7 ++++++-
src/test/recovery/t/003_recovery_targets.pl        |  4 ++--
src/test/recovery/t/006_logical_decoding.pl        |  4 ++--
.../recovery/t/010_logical_decoding_timelines.pl   |  4 ++--
src/test/recovery/t/013_crash_restart.pl           |  2 +-
src/test/recovery/t/017_shm.pl                     | 13 ++++++------
src/test/recovery/t/019_replslot_limit.pl          |  2 +-
14 files changed, 53 insertions(+), 39 deletions(-)