feat: add canvas integration support

[arslanashraf7]

Related ticket

https://github.com/mitodl/edx-platform/issues/299

What this PR does?

• Cherry-picks the Canvas integration from Nutmeg to Olive (Mentioned in the ticket)
• Refactors the code a little to fix the conflicts

How should this be tested?

• Install https://github.com/mitodl/open-edx-plugins/tree/main/src/ol_openedx_canvas_integration (Follow the readme instructions) or just pip install ol-openedx-canvas-integration

• Restart edx instance, notice you are able to see the Canvas tab under Instructor Dashboard

• Set canvas course id in your test course through Studio's Advanced Settings

• Make sure that all the Canvas functionality works fine (Functionality is mostly mentioned in https://github.com/mitodl/open-edx-plugins/tree/main/src/ol_openedx_canvas_integration)

• You will need values for (You can ask for these keys from me or Devops folks):

  • CANVAS_BASE_URL
  • CANVAS_ACCESS_TOKEN

• Some more testing instructions are on https://github.com/mitodl/edx-platform/pull/274

[arslanashraf7]

There are two checks failing but they are not related to any changes in this PR, The same is also failing on our fork on master and I suspect they are related to the environment the checks are running in so they shouldn't effect us.