pgsql: Add missing EmitWarningsOnPlaceholders() calls.

Add missing EmitWarningsOnPlaceholders() calls.

Extensions that define any custom GUCs should call
EmitWarningsOnPlaceholders after doing so, to help catch misspellings.
Many of our contrib modules hadn't gotten the memo on that, though.

Also add such calls to src/test/modules extensions that have GUCs.
While these aren't really user-facing, they should illustrate good
practice not faulty practice.

Shinya Kato

Discussion: https://postgr.es/m/524fa2c0a34f34b68fbfa90d0760d515@oss.nttdata.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1fada5d81e6769ded832a4ca62ee9371bac3fb9f

Modified Files
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contrib/auth_delay/auth_delay.c | 3 +++
contrib/pg_trgm/trgm_op.c | 2 ++
contrib/postgres_fdw/option.c | 2 ++
contrib/sepgsql/hooks.c | 2 ++
src/backend/utils/misc/guc.c | 7 +++++++
src/pl/tcl/pltcl.c | 3 +++
src/test/modules/delay_execution/delay_execution.c | 2 ++
src/test/modules/ssl_passphrase_callback/ssl_passphrase_func.c | 3 +++
src/test/modules/worker_spi/worker_spi.c | 2 ++
9 files changed, 26 insertions(+)