Document the "execute_sql" permission

[toolness]

Hello! I noticed that the "security" section of the documentation says the following:

Access to the dashboard is controlled by Django’s permissions system, which means you can limit access to trusted team members.

However, it doesn't mention what the permission is called. From looking at the source, it appears this permission is called execute_sql:

django-sql-dashboard/django_sql_dashboard/models.py

Line 83 in fe7ff4e

permissions = [("execute_sql", "Can execute arbitrary SQL queries")]

Should this permission be mentioned by name in the documentation? And should the "quick start" mention it too? Or is it already mentioned somewhere and I just missed it?