Fix a missed reference to moved arrow-vector test classes

Author: jduo

java/dataset/src/test/java/org/apache/arrow/dataset/TestAllTypes.java

@@ -32,7 +32,6 @@
 import org.apache.arrow.dataset.file.DatasetFileWriter;
 import org.apache.arrow.dataset.file.FileFormat;
 import org.apache.arrow.memory.BufferAllocator;
-import org.apache.arrow.util.ArrowTestDataUtil;
 import org.apache.arrow.vector.BigIntVector;
 import org.apache.arrow.vector.BitVector;
 import org.apache.arrow.vector.DateMilliVector;
@@ -76,6 +75,7 @@
 import org.apache.arrow.vector.types.pojo.Field;
 import org.apache.arrow.vector.types.pojo.FieldType;
 import org.apache.arrow.vector.types.pojo.Schema;
+import org.apache.arrow.vector.util.ArrowTestDataUtil;
 import org.apache.arrow.vector.util.ByteArrayReadableSeekableByteChannel;
 import org.apache.arrow.vector.util.Text;
 import org.junit.ClassRule;