Merge LocalFileReader and HDFSFileReader

The code is as follows：
```
public class HadoopAndLocalReadTest {

private static final long BUF_SIZE = 4 * 1024 *1024;

@Test
public void testHadoopReadLocal() throws IOException {

long startTime=System.nanoTime();

Path file = new Path("file:///Downloads/index-00001");
Configuration conf = new Configuration();
FileSystem fs = FileSystem.get(conf);

FSDataInputStream getIt = fs.open(file);
BufferedReader d = new BufferedReader(new InputStreamReader(getIt),
(int) BUF_SIZE);
String lineTxt = null;
while ((lineTxt = d.readLine()) != null) {
}
long endTime=System.nanoTime();
System.out.println("The elapsed time of Hadoop： " + (endTime - startTime) + "ns");
d.close();
fs.close();

}

@Test
public void testReadLocal() throws IOException {
long startTime=System.nanoTime();
String filePath = "/Downloads/index-00001";
File file = new File(filePath);
InputStreamReader read = new InputStreamReader(
new FileInputStream(file));
BufferedReader bufferedReader = new BufferedReader(read, (int) BUF_SIZE);

String lineTxt = null;
while ((lineTxt = bufferedReader.readLine()) != null) {
}
long endTime=System.nanoTime();
System.out.println("The elapsed time of local ： " + (endTime - startTime) + "ns");
bufferedReader.close();
read.close();

}
}
```

The number of test sample lines is 47352788.

The test results are as follows：

| BUF_SIZE | The elapsed time of Hadoop FS | The elapsed time of local|
|-----------|---------------------------------|--------------------------|
| 1M | 7531287724ns | 5878985850ns |
| 2M | 7434749749ns | 6601452869ns |
| 4M | 7262694142ns | 6601452869ns |

Conclusion：
We can use Hdfsfilereader to write local files instead of Localfilereader

Start by locating the LocalFileReader and HDFSFileReader implementations and review HadoopAndLocalReadTest, especially testHadoopReadLocal and testReadLocal. Compare their local-file behavior and benchmark assumptions, then define completion as a single reader approach that preserves the required reading behavior and passes the relevant tests.

Written by the indexing model from the issue text.