Follow constraint guidelines for EDXAPP_EXTRA_REQUIREMENTS

[robrap]

We'd like to follow the edx-platform constraint guidelines for the constraints in EDXAPP_EXTRA_REQUIREMENTS in edx-internal (and maybe edge-internal).

Since the constraints are duplicated for prod and stage, consider having a general stage comment that refers to prod constraints for more detailed constraint comments, rather than duplicating and getting out of sync.

[huniafatima-arbi]

Hey @robrap, I have raised a PR and linked to the issue. The date when the package last updated has been added. Although as most of the packages are pinned as their update is handled manually, creating an issue to unpin the constraint and adding reason to pin seemed superfluous.
Please give a review to the PR linked.