Update: documentation for the Chaoscenter Authentication REST API

[namkyu1999]

Proposed changes

This PR updates authentication api document from v2.0.0 to v3.14.0

Changes contain...

• Change the documentation generation tool from spectacle to redoc. Because spectacle does not update anymore. The last commit was 3 years ago.
• add omitted APIs
• add descriptions and fix typos

Demo Links is here: https://namkyu-park99.github.io/litmus/auth/v3.14.0/api.html

Resolves #4771 litmuschaos/litmus-docs#296
ref #4910

Types of changes

What types of changes does your code introduce to Litmus? Put an x in the boxes that apply

• New feature (non-breaking change which adds functionality)
• Bugfix (non-breaking change which fixes an issue)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices applies)

Checklist

Put an x in the boxes that apply. You can also fill these out after creating the PR. If you're unsure about any of them, don't hesitate to ask. We're here to help! This is simply a reminder of what we are going to look for before merging your code.

• I have read the CONTRIBUTING doc
• I have signed the commit for DCO to be passed.
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works (if appropriate)
• I have added necessary documentation (if appropriate)

Dependency

• Please add the links to the dependent PR need to be merged before this (if any).

Special notes for your reviewer:

[jemlog]

Hi @namkyu1999, It’s really a trivial point but I think it's better to unify the capitalization.
For example, other MessageResponses are using 'successful' but here is 'Successful'. 🙂

[namkyu1999]

Yes, I understand your opinion. However, in this PR, I want to ensure that the return values remain unchanged.

[jemlog]

LGTM

[Saranya-jena]

@namkyu1999 could you please check the unit test, one of them is failing.

[namkyu1999]

done @Saranya-jena