StringUtils corrected the right package

Author: joviegas

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/internal/document/DefaultEnhancedDocument.java

@@ -20,7 +20,6 @@
 import static software.amazon.awssdk.enhanced.dynamodb.internal.document.JsonStringFormatHelper.addEscapeCharacters;
 import static software.amazon.awssdk.enhanced.dynamodb.internal.document.JsonStringFormatHelper.stringValue;
 
-import com.amazonaws.util.StringUtils;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
@@ -49,8 +48,10 @@
 import software.amazon.awssdk.protocols.jsoncore.JsonNodeParser;
 import software.amazon.awssdk.services.dynamodb.model.AttributeValue;
 import software.amazon.awssdk.utils.Lazy;
+import software.amazon.awssdk.utils.StringUtils;
 import software.amazon.awssdk.utils.Validate;
 
+
 /**
  * Default implementation of {@link EnhancedDocument} used by the SDK to create Enhanced Documents. Attributes are initially saved
  * as a String-Object Map when documents are created using the builder. Conversion to an AttributeValueMap is done lazily when
@@ -399,7 +400,7 @@ public Builder putJson(String attributeName, String json) {
 
         @Override
         public Builder remove(String attributeName) {
-            Validate.isTrue(!StringUtils.isNullOrEmpty(attributeName), "Attribute name must not be null or empty");
+            Validate.isTrue(!StringUtils.isEmpty(attributeName), "Attribute name must not be null or empty");
             nonAttributeValueMap.remove(attributeName);
             return this;
         }