Team admins unable to create or edit alerts

### Environment

SaaS (https://sentry.io/)

### Steps to Reproduce

1. Disable the option "Let Members Create and Edit Alerts"
2. Add a "Member" to a "Team A" as a "Team Admin"
3. Try to create or edit an alert for any project associated with "Team A"

### Expected Result

The member is able to create and/or edit alerts for all projects from Team A

### Actual Result

The action fails with UI message "Unknown error while saving". The network logs shows a 403 response from the "/api/0/organizations/{organization_id_or_slug}/workflows/{workflow_id}/"

This is caused by the option "Let Members Create and Edit Alerts" removing the `alerts:write` scope from members and setting the user as a Team Admin does not add the scope for the specific team.

### Product Area

Alerts

### Link

_No response_

### DSN

_No response_

### Version

_No response_

Start by tracing the permissions handling for the /api/0/organizations/{organization_id_or_slug}/workflows/{workflow_id}/ endpoint and the alerts:write scope when the organization option is disabled. Reproduce the 403 with a Team Admin who is a Member, then verify that Team Admins can create and edit alerts for their team's projects while regular members remain restricted.

Written by the indexing model from the issue text.