pgsql: Change publication's publish_generated_columns option type to en

Change publication's publish_generated_columns option type to enum.

The current boolean publish_generated_columns option only supports a
binary choice, which is insufficient for future enhancements where
generated columns can be of different types (e.g., stored or virtual). The
supported values for the publish_generated_columns option are 'none' and
'stored'.

Author: Vignesh C <vignesh21(at)gmail(dot)com>
Reviewed-by: Peter Smith <smithpb2250(at)gmail(dot)com>
Reviewed-by: Peter Eisentraut <peter(at)eisentraut(dot)org>
Reviewed-by: Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>
Discussion: https://postgr.es/m/d718d219-dd47-4a33-bb97-56e8fc4da994@eisentraut.org
Discussion: https://postgr.es/m/B80D17B2-2C8E-4C7D-87F2-E5B4BE3C069E@gmail.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/e65dbc9927fb86aa3c8a914ede6a6ae934384f5a

Modified Files
--------------
doc/src/sgml/catalogs.sgml | 14 +++
doc/src/sgml/ref/create_publication.sgml | 29 +++--
src/backend/catalog/pg_publication.c | 36 +++++-
src/backend/commands/publicationcmds.c | 68 ++++++++---
src/backend/replication/logical/proto.c | 66 ++++++----
src/backend/replication/pgoutput/pgoutput.c | 36 +++---
src/backend/utils/cache/relcache.c | 2 +-
src/bin/pg_dump/pg_dump.c | 17 +--
src/bin/pg_dump/pg_dump.h | 3 +-
src/bin/pg_dump/t/002_pg_dump.pl | 4 +-
src/bin/psql/describe.c | 20 +++-
src/include/catalog/catversion.h | 2 +-
src/include/catalog/pg_publication.h | 26 +++-
src/include/commands/publicationcmds.h | 2 +-
src/include/replication/logicalproto.h | 11 +-
src/test/regress/expected/publication.out | 179 +++++++++++++++-------------
src/test/regress/sql/publication.sql | 41 ++++---
src/test/subscription/t/011_generated.pl | 67 ++++++-----
src/tools/pgindent/typedefs.list | 1 +
19 files changed, 394 insertions(+), 230 deletions(-)