change definition of isArithmetic

Author: SizzinSeal

include/units/units.hpp

@@ -132,8 +132,8 @@ template <typename Q>
 concept isQuantity = requires(Q q) { quantityChecker(q); };
 
 // isArithmetic concept
-template <typename Q>
-concept isArithmetic = std::is_arithmetic_v<Q> || isQuantity<Q>;
+template <typename T>
+concept isArithmetic = std::is_arithmetic_v<T>;
 
 // Isomorphic concept - used to ensure unit equivalency
 template <typename Q, typename... Quantities>