Add best practice page

[mtrezza]

New Feature / Enhancement Checklist

• I am not disclosing a vulnerability.
• I am not just asking a question.
• I have searched through existing issues.

Current Limitation

Although the topic pops up frequently, there is no security and common design best practice document.

Feature / Enhancement Description

Add such a page.

Example Use Case

n/a

Alternatives / Workarounds

n/a

3rd Party References

n/a

[github-actions]

🤖 Parsy

Thanks for opening this issue!

• 🎉 We are excited about your ideas for improvement!

I'm in beta, so forgive me if I'm still making mistakes.

[mtrezza]

Closed via parse-community/docs#845