ext/pgsql: fix pg_close_stmt() signature. (#18194)

Author: devnexen

ext/pgsql/pgsql.stub.php

@@ -971,7 +971,7 @@ function pg_socket_poll($socket, int $read, int $write, int $timeout = -1): int
     function pg_set_chunked_rows_size(PgSql\Connection $connection, int $size): bool {}
 #endif
 #ifdef HAVE_PG_CLOSE_STMT
-    function pg_close_stmt(Pgsql\Connection $connection, string $statement_name): Pgsql\Result|false {}
+    function pg_close_stmt(Pgsql\Connection $connection, string $statement_name): PgSql\Result|false {}
 #endif
 }