[COMMITTERS] pgsql: Don't build full initial logical decoding snapshot ifNOEXPORT_S

Don't build full initial logical decoding snapshot if NOEXPORT_SNAPSHOT.

Earlier commits (56e19d938dd14 and 2bef06d5164) make it cheaper to
create a logical slot if not exporting the initial snapshot.  If
NOEXPORT_SNAPSHOT is specified, we can skip the overhead, not just
when creating a slot via sql (which can't export snapshots).  As
NOEXPORT_SNAPSHOT has only recently been introduced, this shouldn't be
backpatched.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ab9c43381ef7a7333086107847413e0b593854d0

Modified Files
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src/backend/replication/walsender.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)