apexDomain returns None for IDNs and FQDNs

[ruurtjan]

Describe the bug
The DomainName#apexDomain function returns None for two types of domain names that are valid, and have a suffix listed in PublicSuffixes.scala:

1. punycode IDNs
2. Fully qualified domain names (domain names with a trailing dot)

Reference:

• https://www.icann.org/ar/registry-agreements/details/xn--6frz82g

• scala-uri/shared/src/main/scala/io/lemonlabs/uri/inet/PublicSuffixes.scala

  Line 7288 in 0602953

  "移动",

To Reproduce

object ApexBugs extends App {

  // This works fine:

  println(DomainName.parseOption("www.example.移动"))
  // Some("www.example.移动")
  
  println(DomainName.parseOption("www.example.移动").get.apexDomain)
  // Some("example.移动")


  // This fails:

  println(DomainName.parseOption("www.example.xn--6frz82g"))
  // Some("www.example.xn--6frz82g")

  println(DomainName.parseOption("www.example.xn--6frz82g").get.apexDomain)
  // None

  println(DomainName.parseOption("www.example.com."))
  // Some("www.example.com.")

  println(DomainName.parseOption("www.example.com.").get.apexDomain)
  // None

}

[ruurtjan]

The workaround for this — if anyone comes across this as well — is to check and strip the dot at the end, and convert the domain name to unicode before calling .apexDomain.

java.net.IDN.toUnicode("www.example.xn--6frz82g")