Add rate limiting to /api/v1/users/sign_in endpoint

[7riumph]

Part of epic #3942

What type of user does this affect?

• volunteers

How should it operate? ⚙️🛠️

Endpoint should now have rate limits.

No more than 5 requests every 60 seconds is allowed to /api/v1/users/sign_in from a given ip or email.

Acceptance Criteria

• ip is throttled on the above criteria in config/initializers/rack_attack.rb
• Email is throttled on the above criteria config/initializers/rack_attack.rb

Helpful Links

Rake::Attack Documentation ( Scroll down to "Throttling" header )
Rake::Attack file in this Codebase

[Raushan998]

@7riumph I want to try on this.

[xihai01]

@Raushan998 these issues are reserved for another dev group to work on - codethechange