This change creates a context that mimics the Mistral context. This
allows us to short-circuit and cut Mistral out, calling the Python
action directly.
All plan list actions have been updated to use this new process and
the old mistral function has been deleted.
Story: 2007247
Task: 38594
Depends-On: https://review.opendev.org/#/c/706196/
Change-Id: I463b5e3d1c4c15dd859a841d65a5057716f84208