pgsql: pg_recvlogical: Honor source cluster file permissions for output

pg_recvlogical: Honor source cluster file permissions for output files

Commit c37b3d08ca6 attempted to preserve group permissions on pg_recvlogical
output files when group access was enabled on the source cluster. However,
the output files were still created with a fixed S_IRUSR | S_IWUSR mode,
preventing group-read permissions from being applied.

This commit fixes the issue by creating output files with pg_file_create_mode
instead of a hard-coded mode. This allows pg_recvlogical to correctly preserve
group permissions from the source cluster.

Backpatch to all supported branches.

Author: Fujii Masao <masao(dot)fujii(at)gmail(dot)com>
Reviewed-by: Srinath Reddy Sadipiralla <srinath2133(at)gmail(dot)com>
Discussion: https://postgr.es/m/CAHGQGwHhpizYzMo3nFP4GkNMueSNMY3QfC-gBN1VTXtuiANDvw@mail.gmail.com
Backpatch-through: 14

Branch
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REL_18_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/89b4b3ae35d2f38aa0e12b147c92c99262c6d146

Modified Files
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doc/src/sgml/ref/pg_recvlogical.sgml | 2 +-
src/bin/pg_basebackup/pg_recvlogical.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)