pgsql: Doc: fix column list vs. replica identity rules.

Doc: fix column list vs. replica identity rules.

It was not strictly correct to say that a column list must always include
replica identity columns because that is true for only updates and
deletes.

Author: Peter Smith
Reviwed-by: Vignesh C, Amit Kapila
Backpatch-through: 15, where it was introduced
Discussion: https://postgr.es/m/CAHut+PvOuc9=_4TbASc5=VUqh16UWtFO3GzcKQK_5m1hrW3vqg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/376af686111e57929c626254eb403c0e810d8e22

Modified Files
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doc/src/sgml/ref/create_publication.sgml | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)