pgsql: Constistent naming for datacheckusms processes

Constistent naming for datacheckusms processes

The launcher and worker for enabling/disabling checksums were named
"datachecksum worker|launcher" but using the plural form makes more
sense given the underlying GUC name data_checksums.

Author: Daniel Gustafsson <daniel(at)yesql(dot)se>
Reported-by: Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com>
Discussion: https://postgr.es/m/20260528.121622.1662808269492494574.horikyota.ntt@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5ab239c9a908ba5d8614d23fcdc425859a2fed3c

Modified Files
--------------
src/backend/postmaster/datachecksum_state.c | 8 +++---
src/include/postmaster/proctypelist.h | 4 +--
src/test/modules/test_checksums/t/002_restarts.pl | 6 ++--
.../test_checksums/t/003_standby_restarts.pl | 2 +-
.../test_checksums/t/DataChecksums/Utils.pm | 4 +--
src/test/regress/expected/stats.out | 32 +++++++++++-----------
6 files changed, 28 insertions(+), 28 deletions(-)