Fix two Gauava 20 deprecations across the tools package

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=146162927

java/google/registry/tools/AppEngineConnection.java

@@ -148,7 +148,7 @@ class AppEngineConnection implements Connection {
   }
 
   boolean isLocalhost() {
-    return flags.getServer().getHostText().equals("localhost");
+    return flags.getServer().getHost().equals("localhost");
   }
 
   private String getUserId() {