Don't use the Maven name "target" for a test fixture to avoid confusion

Even though, in this specific case, the actual directory is not the
Maven "target" folder.

Author: garydgregory

src/test/java/org/apache/commons/io/FileUtilsTest.java

@@ -925,7 +925,7 @@ void testCopyDirectoryPreserveDates() throws Exception {
         assertTrue(setLastModifiedMillis(sourceDirectory, DATE2));
         assertTrue(setLastModifiedMillis(source, DATE1));
 
-        final File target = new File(tempDirFile, "target");
+        final File target = new File(tempDirFile, "dest");
         final File targetDirectory = new File(target, "directory");
         final File targetFile = new File(targetDirectory, "hello.txt");