fix: usr: Fix recursion loop in case of badly behaving forwarders

When forwarding DNS queries, the CD bit is cleared on the first query, and the CD bit is only used as a fallback if the first query fails. However, due to a logic bug this could lead to an unbounded loop re-sending the same message, until the maximum query count is hit. This has been fixed.

Closes #5804

Merge branch '5804-resend-loop-forwarder-cd' into 'main'

See merge request isc-projects/bind9!12133