pgsql: postgres_fdw: Update comments in make_new_connection().

postgres_fdw: Update comments in make_new_connection().

Expand the comment about the parallel_commit option to mention that the
default is false.

Also, since the comment about alteration of the keep_connections option,
which was located above the expanded comment, holds true for the
parallel_commit option, rewrite it to reflect this, and move it to after
the expanded comment.

Follow-up for commit 04e706d42.

Discussion: /messages/by-id/CAPmGK16Kg2Bf90sqzcZ4YM5cN_G-4h7wFUS01qQpqNB+2BG5_w@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4036bcbbb92839f20ed6d0db418996954dd66470

Modified Files
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contrib/postgres_fdw/connection.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)