Change second-level domain name to fully-qualified domain name

Second-level domain name isn't accurate because we support multi-part
TLDs, so standardize on the "fullyQualifiedDomainName" name that is
used throughout the code base.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=122693009

javatests/google/registry/tools/GetApplicationIdsCommandTest.java

@@ -62,7 +62,7 @@ public class GetApplicationIdsCommandTest extends CommandTestCase<GetApplication
 
   @Test
   public void testFailure_tldDoesNotExist() throws Exception {
-    thrown.expect(NullPointerException.class);
+    thrown.expect(IllegalArgumentException.class, "Domain name is not under a recognized TLD");
     runCommand("example.foo");
   }