pgsql: Only show signal-sender PID/UID detail in server log

Only show signal-sender PID/UID detail in server log

The errdetail() added in 55890a91945 (and reworked in 3e2a1496bae)
exposed the operating-system PID and UID of whoever sent the
termination signal directly to the affected client.

Discussion suggested this should not be sent to the client, but only
recorded in the server log where the admin can use it for diagnosis.

Author: Chao Li <li(dot)evan(dot)chao(at)gmail(dot)com>
Reviewed-by: Jakub Wartak <jakub(dot)wartak(at)enterprisedb(dot)com>
Discussion: https://postgr.es/m/E5CA274C-74BD-4067-8B73-A3AD8C080EFA@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b772f3fcad1870731020dbe56713c616abc5dc26

Modified Files
--------------
src/backend/replication/syncrep.c | 7 ++++---
src/backend/tcop/postgres.c | 7 ++++---
src/bin/psql/t/001_basic.pl | 2 +-
3 files changed, 9 insertions(+), 7 deletions(-)