[9.18] new: usr: Add a new option to configure the maximum number of outgoing queries...

[9.18] new: usr: Add a new option to configure the maximum number of outgoing queries per client request

The configuration option 'max-query-count' sets how many outgoing queries per client request is allowed. The existing 'max-recursion-queries' is the number of permissible queries for a single name and is reset on every CNAME redirection. This new option is a global limit on the client request. The default is 200.

This allows us to send a bit more queries while looking up a single name. The default for 'max-recursion-queries' is changed from 32 to 50.

Closes #4980 Closes #4921

Backport of MR !9737

Merge branch 'backport-4980-global-limit-outgoing-queries-9.18' into 'bind-9.18'

See merge request isc-projects/bind9!9847