Remove duplicate test class.

library/src/androidTest/java/com/bumptech/glide/load/model/NullResourceEncoderTest.java

-package com.bumptech.glide.load.model;
-
-import com.bumptech.glide.load.engine.Resource;
-import com.bumptech.glide.load.resource.NullResourceEncoder;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-import java.io.ByteArrayOutputStream;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.mockito.Mockito.mock;
-
-@RunWith(JUnit4.class)
-public class NullResourceEncoderTest {
-    private NullResourceEncoder<Object> encoder;
-
-    @Before
-    public void setUp() {
-        encoder = new NullResourceEncoder<Object>();
-    }
-
-    @Test
-    public void testReturnsFalse() {
-        assertFalse(encoder.encode(mock(Resource.class), new ByteArrayOutputStream()));
-    }
-
-    @Test
-    public void testReturnsEmptyId() {
-        assertEquals("", encoder.getId());
-    }
-}
\ No newline at end of file