add instructions for setting up cicd deploy keys on instructors repos

[buedaswag]

Context: We should have instructions for setting up cicd deploy keys on instructors repos. These instructions should live on the wiki and be linked into each instructors repo (ex: https://github.com/LDSSA/batch6-instructors, https://github.com/LDSSA/ds-prep-course-instructors-2022, https://github.com/LDSSA/batch6-admissions-instructors)

instructions

• Go to circleci of the instructors repo - https://app.circleci.com/settings/project/github/LDSSA/batch6-instructors
• Make sure your github user is able to create branches and push to branches on the students repo
• 
• This will create a deploy key on your user profile that will allow circle ci to act on your behalf to deploy the code to the students repo

Goal(s):

• create instructions page or section in the wiki, as a pull request, merge the pull request
• link the instructions on all the relevant repos, as a pull request for each repo, merge the pull request for each repo

Acceptance criteria: goals are accomplished