Skip domain approval logic if host is invalid

The collection logic for exposing HTTP domains only accepts those
that match Patterns#DOMAIN_NAME, roughly "domain.tld".

This updates the Intent resolution logic to match so that link approval
is not required if the URI host doesn't match that pattern.

Bug: 184963244

Test: atest DomainVerificationValidIntentTest
Test: atest CtsDomainVerificationDeviceTestCases

Change-Id: Ieb4ca01089785246b61d6b1710d76bffceefcbf7