Stop the logger properly in legacy commands

Ensures the logger is stopped on exit in legacy commands. Without this,
when using `nix-build --log-format bar` and stopping nix with CTRL+C,
the bar is not cleared from the screen.

src/nix-store/nix-store.cc

@@ -1095,8 +1095,6 @@ static int main_nix_store(int argc, char * * argv)
 
         op(opFlags, opArgs);
 
-        logger->stop();
-
         return 0;
     }
 }