DOJO(mentor): Create exercises page

[flacial]

Create the following page

Required components to be created:

• Preview card

Components to be created within the page:

• Inputs form
• Dropdown to switch the lesson module

Misc:

• The page will be accessed through /mentor/[lessonSlug]/[moduleSlug]/exercise (could be discussed with engs)

[evo777]

Good feature.