Added behave framework

[king0ffire]

Made following changes:

• Added a static folder with css and js files to support the homepage. (Fixbug)
• Changed dockerfile and poetry-related files to support behave commands.
• Added 2 step files as BDD behaviours.
• Added find_by_restocking_available function to the model.
• Added structures of rest_api.js. (Not guaranteed to work)

Remeber to rebuild your docker container on your local machine before test this PR.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark: