* fix(netxlite): make default resolver converge faster
Closes https://github.com/ooni/probe/issues/1726
* Update internal/netxlite/resolver.go
* fix(ndt7): adapt tests after previous change
Because now we're running the DNS resolution inside a goroutine
with a child context, the returned error string is different.
The previous error said we canceled the whole dialing operation,
while now we see directly that the context was canceled.