Remove edXRestApiClient usage across the Open edX platform and replace it with OAuthAPIClient

[jmakowski1123]

tCRIL Funded Contribution: Context & Background

This deprecation work is being undertaken as part of a General Deprecation project funded by tCRIL to expedite a backlog of deprecation debt. The goal of this project is to finish the removal of several unfinished deprecation tickets that we have not been able to complete ourselves due to time constraints.

Project-level metrics:

Impact: Ease of development/time to market.
Measure: DEPR tickets moved to 'Removed' and LOC removed.

We have many deprecation projects in the pipeline and that have been announced to the community, but we don't have the resources to remove all the technology ourselves. We have allotted a general bucket of hours that we can devote to deprecation work to help reduce the pain and complexity of this 'dead' code for future engineers. There are a few general categories of deprecations that we have chosen to focus on:

Unsupported libraries
Multiple versions of the same feature
Incomplete migrations
MFE replacement work

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Remove EdXRestApiClient usage across the Open edX platform and replace it with the OAuthAPIClient

[see: DEPR https:/openedx/public-engineering/issues/37]

Scope & Approach

EdXRestApiClient is no longer supported. Unsupported libraries(slumber) create potential security concerns and must be replaced.

Value & Impact

Removes dependencies on unsupported libraries and reduces security risk.

Milestones and/or Epics

See: openedx/public-engineering#37

Named Release

Nutmeg

Timeline

See: openedx/public-engineering#37

Proposed By

tCRIL

[github-actions]

Thanks for your submission, @openedx/open-edx-project-managers will review shortly.

[feanil]

@jmakowski1123 FYI, this work has been completed.