wmr-SRP example for class and minor UI update on MyHall

[jtasonye]

Changes made in PR:

• Following the Single Responsibility Principle in React, I changed the logic used to generate the RD Link for the MyHall component. SRP states that a component should have one clear responsibility, but looking at our previous useEffect, it had multiple responsibilities (e.g. string manipulation and updating the state setRdProfileLink).
• By implementing the following fix, generateRDProfileLink is only responsible for the string manipulation to get the profile link and the useEffect is only responsible for state updates now
• Also, I realized that the My Assigned Rooms text should only be displayed if the user is an RA, so I made some changes to fix that error