Revisit FormattedQuantityDescription and it's subclasses

[hl662]

After introducing helper methods to retrieve formatting Specs through https://github.com/iTwin/itwinjs-core/pull/8082 , and deprecating quantityType in PropertyDescription, we'd like to re-evaluate FormattedQuantityDescription and it's subclasses in core-frontend.

The formatting and parsing should be handled on the UI layer, and these subclasses shouldn't need to hold information about the specs. The parent issue of the PR above explained how these classes can 'introduce unnecessary complexity and confusion'.

One idea brought up was to replace all these subclasses of FormattedQuantityDescription with helper methods like createAngleDescription, createLengthDescription etc, and return either a PropertyDescription interface or a BaseQuantityDescription class. While BaseQuantityDescription is an abstract class, the abstract properties formatterQuantityType and parseError should be removed since we're removing parsing/formatting logic from these Description classes. The subclasses for FormattedQuantityDescription will be deprecated.

Another option is to forgo creating instance of classes entirely, and refactoring our code to populate a PropertyDescription object, instead of instancing a class implementing PropertyDescription (like FormattedQuantityDescription). All the subclasses implementing PropertyDescription could be marked for deprecation.