Do not escape WHOIS output

Both WhoisAction and WhoisHttpAction set the HTTP response content type to "text/plain". There is no need to defensively escape the content. In fact, by escaping the content, it creates more problems down the line.

When used in a website, the response should be written into a DOM node by setting the textContent of the node, which automatically escapes the content.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=196743398

javatests/google/registry/whois/DomainWhoisResponseTest.java

@@ -117,7 +117,7 @@ public class DomainWhoisResponseTest {
             new PostalInfo.Builder()
             .setType(PostalInfo.Type.INTERNATIONALIZED)
             .setName("EXAMPLE REGISTRANT")
-            .setOrg("EXAMPLE ORGANIZATION")
+            .setOrg("Tom & Jerry Corp.")
             .setAddress(new ContactAddress.Builder()
                 .setStreet(ImmutableList.of("123 EXAMPLE STREET"))
                 .setCity("ANYTOWN")