pgsql: Cleanup perl code from unused variables and routines

Cleanup perl code from unused variables and routines

This commit removes unused variables and routines from some perl code
that have accumulated across the years.  This touches the following
areas:
- Wait event generation script.
- AdjustUpgrade.pm.
- TAP perl code

Author: Alexander Lakhin
Reviewed-by: Dagfinn Ilmari Mannsåker
Discussion: https://postgr.es/m/70b340bc-244a-589d-ef8b-d8aebb707a84@gmail.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/0c1aca461481216ff5a0e65538c4880bcf346433

Modified Files
--------------
contrib/amcheck/t/001_verify_heapam.pl                    | 15 +--------------
contrib/amcheck/t/002_cic.pl                              |  2 +-
src/backend/utils/activity/generate-wait_event_types.pl   |  2 --
src/bin/pg_dump/t/003_pg_dump_with_server.pl              |  1 -
src/bin/pg_dump/t/005_pg_dump_filterfile.pl               |  1 -
.../ldap_password_func/t/001_mutated_bindpasswd.pl        |  4 ----
.../modules/ssl_passphrase_callback/t/001_testfunc.pl     |  1 -
src/test/perl/PostgreSQL/Test/AdjustUpgrade.pm            |  1 -
src/test/recovery/t/021_row_visibility.pl                 |  1 -
src/test/recovery/t/032_relfilenode_reuse.pl              |  1 -
src/test/recovery/t/035_standby_logical_decoding.pl       |  5 +----
11 files changed, 3 insertions(+), 31 deletions(-)