IO/config: remove unneeded destructor definition

Author: andrea-iob

src/IO/configuration_config.cpp

@@ -78,13 +78,6 @@ Config & Config::operator=(Config other)
     return *this;
 }
 
-/*!
-    Destructor.
-*/
-Config::~Config()
-{
-}
-
 /*!
     Swap operator.
 

src/IO/configuration_config.hpp

@@ -48,7 +48,7 @@ class Config
     Config & operator=(Config other);
     Config & operator=(Config &&other) = default;
 
-    virtual ~Config();
+    virtual ~Config() = default;
 
     void swap(Config &other);