pgsql: Fix comment in libpqrcv_check_conninfo().

Fix comment in libpqrcv_check_conninfo().

Previously, the comment incorrectly stated that libpqrcv_check_conninfo()
returns true or false based on the connection string check.
However, this function actually has a void return type and
raises an error if the check fails.

Author: Rintaro Ikeda
Reviewed-by: Jelte Fennema-Nio, Fujii Masao
Discussion: https://postgr.es/m/6a1ca81b27fec4da0ccdfaaaec787982@oss.nttdata.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/629520be5f9da9d0192c7f6c8796bfddb4746760

Modified Files
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src/backend/replication/libpqwalreceiver/libpqwalreceiver.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)