Update Array prototypes lesson

[wvmitchell]

Lesson to be updated: Array Prototypes

Summary of changes needed:

• Currently this lesson is being utilized as a 'self-teach' activity
• Given our new functional emphasis, it makes sense to have an actual lesson on this
• Review the lesson creation guidelines, and ensure that the lesson plan meets those criteria

Lesson creation guidelines (also on FE Hub

• Lesson Preparation Foundations
• 4 Pillars of Remote Instruction
• Instructional Values
• Culturally Responsive Teaching

[CassandraGoose]

I can't get this issue to link to the PR for some reason. The PR for this issue is: https://github.com/turingschool/front-end-curriculum/pull/622