Use djstripe models for organization subscriptions

[stsewd]

This is to achieve #9312.

Basically just adding relationship to the Customer model from djstripe, we would need to trigger a resync for .com (since the last time there were some errors due to stripe bug with the logo), after that we can migrate the existing organizations to set the stripe customer on their models, this is done automatically for users that visit the subscription page and for new organizations. I'm not doing this as a data migration, since we would be hitting the stripe API in the process, we can execute this script to migrate them from web extra:

from readthedocs.organizations.models import Organization
from readthedocs.subscriptions.utils import get_or_create_stripe_customer

import logging

log = logging.get_logger(__name__)


def migrate(limit=500):
    queryset = Organization.objects.filter(stripe_customer=None).all()
    if limit:
        queryset = queryset[:limit]
    else:
        queryset = queryset.iterator()
    for organization in queryset:
        try:
            get_or_create_stripe_customer(organization)
        except Exception:
            log.exception(
                "Failed to create stripe customer for %{organization}s",
                organization=organization.slug,
            )

I have tested this locally with stripe's test mode.

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📚 Documentation preview 📚: https://docs--9486.org.readthedocs.build/en/9486/

[stsewd]

we would need to trigger a resync for .com (since the last time there were some errors due to stripe bug with the logo)

This was already done, and all responses from our webhook are all green!

[ericholscher]

This is a great first step. Excited about this transition!

[ericholscher]

Is there more information here? I don't quite understand this comment -- is it disabling some feature of djstripe? Are we going to turn this back on in the future?

[stsewd]

It's disabling the feature, yes (well, partially, since stripe still creates a relationship to the user object), and we won't be using this in the future. I'll expand the comment.

[humitos]

Looks good! I like how the code gets simplified and easier to follow with this package 💯