pgsql: Rename COPY option from SAVE_ERROR_TO to ON_ERROR

Rename COPY option from SAVE_ERROR_TO to ON_ERROR

The option names now are "stop" (default) and "ignore".  The future options
could be "file 'filename.log'" and "table 'tablename'".

Discussion: https://postgr.es/m/20240117.164859.2242646601795501168.horikyota.ntt%40gmail.com
Author: Jian He
Reviewed-by: Atsushi Torikoshi

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b725b7eec431f7394d63abe621170efe3fcdcda4

Modified Files
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doc/src/sgml/ref/copy.sgml           | 20 +++++++++----------
src/backend/commands/copy.c          | 38 ++++++++++++++++++------------------
src/backend/commands/copyfrom.c      | 20 +++++++++----------
src/backend/commands/copyfromparse.c |  6 +++++-
src/bin/psql/tab-complete.c          |  8 ++++----
src/include/commands/copy.h          | 10 +++++-----
src/test/regress/expected/copy2.out  | 36 +++++++++++++++++-----------------
src/test/regress/sql/copy2.sql       | 20 +++++++++----------
src/tools/pgindent/typedefs.list     |  2 +-
9 files changed, 82 insertions(+), 78 deletions(-)