Fix a number of issues with Azure storage

[browniebroke]

Description

• Don't install Collectfasta when Azure is selected as cloud provider
• Fix file_overwrite -> overwrite_files option on Azure storage
• Remove unused nginx configs when a cloud provider is selected

Checklist:

• [x] I've made sure that tests are updated accordingly (especially if adding or updating a template option)
• [x] I've updated the documentation or confirm that my change doesn't require any updates

Rationale

Fix the issue outlined in https://github.com/cookiecutter/cookiecutter-django/discussions/5374