Remove trailing whitespace in files

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=135386752

java/google/registry/tools/params/EnumParameter.java

@@ -16,8 +16,8 @@ package google.registry.tools.params;
 
 import google.registry.util.TypeUtils.TypeInstantiator;
 
-/** Base class for Enum-based parameters. 
- * 
+/** Base class for Enum-based parameters.
+ *
  * <p>This is not necessary for single-value Enum parameters (i.e. arity = 1) as JCommander natively
  * supports them, but is necessary for variable-arity ({@code List&lt;Enum&gt;}) parameters.
  */