feat: add layout with sidebar for dashboard pages #15

[ManojBahuguna]

• add material-ui lib and dependencies (emotion)
• add basic layout for internal dashboard pages

https://github.com/MentorsWithoutBorders/mwb-partners-admin/assets/19573007/fc6eddbc-ef99-4f52-a1dc-6879c8c43901

Note: material-ui already contains styled api, so we shouldn't require styled-components explicitly

Related #15