[added] check for mirror stream return error when de dupe window is set

[matthiashanel]

Signed-off-by: Matthias Hanel [email protected]

Noticed this in natscli, where I removed the interactive question.
For an actual check RI preferred doing this here.

ats --context=hub s add --mirror test --dupe-window=2s
? Stream Name ss
? Storage backend file
? Retention Policy Limits
? Discard Policy Old
? Stream Messages Limit -1
? Message size limit -1
? Maximum message age limit -1
? Maximum individual message size -1
? Replicas 3
? Adjust mirror start No
X Sorry, your reply was invalid: "spoke-1" is not a valid answer, please try again.
? Import mirror from a different JetStream domain Yes
? Foreign JetStream domain name spoke-1
? Delivery prefix
nats: error: could not create Stream: stream mirrors do not make use of a de-duplication window

[derekcollison]

LGTM - Thanks!