remove unused imports

Author: diegomarquezp

google-http-client-test/src/main/java/com/google/api/client/test/json/AbstractJsonGeneratorTest.java

@@ -23,7 +23,6 @@
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Map;
-import junit.framework.TestCase;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;

google-http-client-test/src/main/java/com/google/api/client/test/json/AbstractJsonParserTest.java

@@ -25,7 +25,6 @@
 import java.io.InputStream;
 import java.math.BigDecimal;
 import java.nio.charset.StandardCharsets;
-import junit.framework.TestCase;
 import org.junit.Assert;
 import org.junit.Test;
 import org.junit.runner.RunWith;