Rename WhoisServer and WhoisHttpServer to actions

These servlets are converted to actions during daggerization. Calling them servers are misleading.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=190942237

java/google/registry/config/RegistryConfig.java

@@ -852,7 +852,7 @@ public final class RegistryConfig {
     /**
      * Amount of time public HTTP proxies are permitted to cache our WHOIS responses.
      *
-     * @see google.registry.whois.WhoisHttpServer
+     * @see google.registry.whois.WhoisHttpAction
      */
     @Provides
     @Config("whoisHttpExpires")