some clang-tidy fixes in graphs

alib2graph_algo/src/minimum_cut/FordFulkerson.cpp

@@ -80,7 +80,7 @@ static Cut fordfulkerson_impl_dir(const DirectedGraph &graph,
   }
   // cut are those edges, which lead from nodes reachable from source to nodes unreachable from source
-  for (std::pair<node::Node, node::Node> edge : candidates) {
+  for (const std::pair<node::Node, node::Node> & edge : candidates) {
     if ((state[edge.first] == 1 && state[edge.second] == 0)
         || (state[edge.first] == 0 && state[edge.second] == 1))
       cut.insert(edge);
@@ -120,7 +120,7 @@ static Cut fordfulkerson_impl_undir(const UndirectedGraph &ugraph,
   }
   // cut are those edges, which lead from nodes reachable from source to nodes unreachable from source
-  for (std::pair<node::Node, node::Node> edge : candidates) {
+  for (const std::pair<node::Node, node::Node> & edge : candidates) {
     if ((state[edge.first] == 1 && state[edge.second] == 0)
         || (state[edge.first] == 0 && state[edge.second] == 1))
       cut.insert(edge);

alib2graph_data/src/common/Normalize.hpp

@@ -86,7 +86,7 @@ ext::pair<DefaultCoordinateType, DefaultCoordinateType> Normalize::normalizeObst
                                                                                                TCoordinate> &&obstacle) {
   DefaultCoordinateType first = DefaultCoordinateType(obstacle.first);
   DefaultCoordinateType second = DefaultCoordinateType(obstacle.second);
-  return ext::make_pair(std::move(first), std::move(second));
+  return ext::make_pair(first, second);
 }
 // =====================================================================================================================