Revert "XMLメタデータを読み取るメソッド追加"

This reverts commit d2950ab781.

source/src/main/java/one/nem/lacerta/source/file/impl/FileManagerImpl.java

@@ -107,12 +107,7 @@ public class FileManagerImpl implements FileManager {
 
     @Override
     public XmlMetaModel getXmlMeta() {
-        if (currentDir.resolve("meta.xml").toFile().exists()) {
-            // TODO-rca: XMLを読み込んで返す
-            return null;
-        } else {
-            return null;
-        }
+        return null;
     }
 
     @Override