feat: add single sing on by saml

[RawanMatar89]

Describtion:

as in iOS, we added a new button in sign in view named "Sign in with SSO" to be use for opening single sign on web view

Screenshots:

Before	After (both)	After (SSO only)

[openedx-webhooks]

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[github-advanced-security]

detekt found more than 20 potential problems in the proposed changes. Check the Files changed tab for more details.

[e0d]

@RawanMatar89 it looks like there are some failing tests and checks, can you have a look. We can review this when the checks are passing.

I also want to make sure we ensure this work meshes will with this:

#371

@xitij2000 can you chime in here?

[xitij2000]

@RawanMatar89 it looks like there are some failing tests and checks, can you have a look. We can review this when the checks are passing.

I also want to make sure we ensure this work meshes will with this:

#371

@xitij2000 can you chime in here?

I am currently unable to test the code or have a deeper look; however, I do see some overlap. #371 adds a web-browser based flow that will initiate an OAuth flow with the LMS, delegating the actual login mechanism to whatever IdPs are set up at the LMS including any SAML-based ones. So from what I understand, what this PR is doing is already possible using the existing code.