copy_records_to_table depends on prepared statments even with cache=0

I have to use pg_bouncer in transaction mode, so tried disabling statement cache. However, when using copy_records_to_table, I am still getting prepared statement errors.

Start with the copy_records_to_table entry point and inspect how cache=0 affects statement handling. Reproduce the report using pg_bouncer in transaction mode and verify whether prepared statement errors still occur; done means the operation works without those errors when statement caching is disabled.

Written by the indexing model from the issue text.