Increase the rate of allowed requests

[mpeven]

Increase the amount of requests that an "unauthenticated" user can perform, to prevent throttling errors when using the CLI.

Motivation and context

Hitting the /login endpoint from an unauthenticated user can trigger throttling. While throttling should be kept, as it is good practice, the rate can be increased as the user may have valid authentication. A reasonable level of 100 requests/minute should be enough to enforce good practices while preventing headaches for users trying to automate tasks with the CLI.

(This rate was chosen to be similar to the rate limiting docs for Laravel)

How has this been tested?

Manually.

Checklist

• I submit my changes into the develop branch
• I have added description of my changes into CHANGELOG file
  - [ ] I have updated the documentation accordingly
  - [ ] I have added tests to cover my changes
  - [ ] I have linked related issues (read github docs)
  - [ ] I have increased versions of npm packages if it is necessary (cvat-canvas,
  cvat-core, cvat-data and cvat-ui)

License

• I submit my code changes under the same MIT License that covers the project.
  Feel free to contact the maintainers if that's a concern.
• I have updated the license header for each file (see an example below)

# Copyright (C) 2020 Intel Corporation
#
# SPDX-License-Identifier: MIT

[coveralls]

Pull Request Test Coverage Report for Build 6700

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 5 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.02%) to 69.039%

---

Files with Coverage Reduction	New Missed Lines	%
cvat/apps/engine/media_extractors.py	5	76.11%

Totals
Change from base Build 6698:	-0.02%
Covered Lines:	11177
Relevant Lines:	15673

---

💛 - Coveralls

[mpeven]

@nmanovic if it helps in the review - I discussed this on Gitter with @azhavoro and he agrees this is a correct change to make.

[nmanovic]

@mpeven , thanks for the PR. 👍 Let me think a little bit about the issue. I understand the problem. Your new limit looks reasonable and I don't think that it is a security issue (100 per minute is pretty small). I will come back soon.

[nmanovic]

@mpeven , thanks one more time. Let's use the solution till we have something better.