Store index in BIGINT in "result_entries"

lib/Zonemaster/Backend/DB/PostgreSQL.pm

@@ -103,7 +103,7 @@ sub create_db {
 
     $dbh->do(
         'CREATE TABLE IF NOT EXISTS result_entries (
-            id serial primary key,
+            id BIGSERIAL primary key,
             hash_id VARCHAR(16) not null,
             level varchar(15) not null,
             module varchar(255) not null,