Add pages for Volunteers and Beneficiaries links

[jensren]

What: currently, Volunteers and Beneficiaries on the navbar are not linked to any page. Add two pages and link them in the navbar.

Why: getting started with React. :) We will also be adding to those to pages later, so it is convenient if they are already set up

How:

• Create a VolunteersComponent with a title Volunteers in the volunteers folder under components. Otherwise, the page can be empty
• Create a BeneficiariesComponent with a title Beneficiaries in the beneficiaries folder under components. Otherwise, the page can be empty
• Add a new Route with the exact path "/volunteers" and the VolunteersComponent as the component to App.tsx
• Add a new Route with the exact path "/beneficiaries" and the BeneficiariesComponent as the component to App.tsx