pgsql: Message wording improvements

Message wording improvements

Use "row" instead of "tuple" for user-facing information for
logical replication conflicts.

Branch
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REL_18_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/9d115b9e11f553991badc0148bfa52580d1b3c8f

Modified Files
--------------
doc/src/sgml/logical-replication.sgml      | 28 ++++++++++++++--------------
src/backend/executor/execReplication.c     |  6 +++---
src/backend/replication/logical/conflict.c | 26 +++++++++++++-------------
src/include/replication/conflict.h         |  4 ++--
src/test/subscription/t/001_rep_changes.pl |  4 ++--
src/test/subscription/t/013_partition.pl   |  8 ++++----
src/test/subscription/t/029_on_error.pl    |  2 +-
src/test/subscription/t/030_origin.pl      |  4 ++--
src/test/subscription/t/035_conflicts.pl   | 16 ++++++++--------
9 files changed, 49 insertions(+), 49 deletions(-)