rm Coordinate copy c'tor, not needed

Base/Axis/Coordinate.cpp

@@ -51,8 +51,6 @@ Coordinate::Coordinate(const std::string& label)
 {
 }
 
-Coordinate::Coordinate(const Coordinate& coord) = default;
-
 std::string Coordinate::label() const
 {
     return name() + " (" + unit() + ")";

Base/Axis/Coordinate.h

@@ -23,7 +23,6 @@ class Coordinate {
 public:
     Coordinate(const std::string& label);
     Coordinate(const std::string& name, const std::string& unit);
-    Coordinate(const Coordinate& coord);
 
     bool operator==(const Coordinate& other) const = default;