feat: add Hooks Extension Framework tooling for filters #2

[mariajgrimaldi]

Description:

This PR adds the tooling needed by the Hooks Extension Framework to execute filters. This project is described in more depth in the OEP-50.

The tooling consists of a pipeline (Pipeline tooling ADR) that executes a list of functions pre-configured that are associated with the filter via Django settings (Filters configuration ADR).

Dependencies:
The architectural design records where the configuration and pipeline design used by the tooling are defined in Pull Request #2.

Testing instructions:

1. Run make lms-shell
2. Inside the shell run:
   pip install -e git+https://github.com/eduNEXT/openedx-filters.git@MJG/filter_tooling#egg=filter_tooling
3. Run pip install -e https://github.com/eduNEXT/openedx-basic-hooks.git, you can also use your own test library. Here are defined the functions that will be executed by a trigger.
4. Here's a quick and dirty way to create and use filters on edx-platform. In the example we are using pre_register_filter that's soon to be added (PR pending).
5. (Optional) If you're using our demo and sample openedx-base-hooks, you can use our pre_register_filter. What you'll have to do is execute the logic that the filter extended, for example:

• Go to register
• Enter data for registration and in the field Year of birth add 2020 (or any year after 2000).
• Then, an error will be displayed caused by the HookFilterException raised by our filter function defined in this location

Reviewers:

• @morenol
• @felipemontoya

Merge checklist:

• All reviewers approved
• CI build is green
• Version bumped
• Changelog record added
• Documentation updated (not only docstrings)
• Commits are squashed

Post merge:

• Create a tag
• Check new version is pushed to PyPI after tag-triggered build is
  finished.
• Delete working branch (if not needed anymore)

[morenol]

This looks great! I added a couple of comments

[felipemontoya]

I tested this with different filter definitions, different pipeline configurations and different logic for raising exceptions and it performed as we have so long discussed via all the channels.

Thanks @mariajgrimaldi, I think we are ready to merge

[felipemontoya]

Please squash the 10 commits before merging