Dimensions concepts definitions refactored

src/include/units/base_dimension.h

@@ -50,7 +50,6 @@ namespace units {
 template<basic_fixed_string Symbol, Unit U>
   requires U::is_named
 struct base_dimension {
-  using base_type_workaround = base_dimension; // TODO Replace with is_base_dimension when fixed
   static constexpr auto symbol = Symbol;  ///< Unique base dimension identifier
   using base_unit = U;                    ///< Base unit adopted for this dimension
 };