fix: added logout user before sso pipeline starts

[Akanshu-2u]

Description:

Users logging in through OAuth SSO could retain session data from previous logins, creating potential security risks and confusion when switching between accounts.

Solution:

Added logout(request) call in EdXOAuth2.start() method to clear existing sessions before OAuth authentication begins.

JIRA:

BOMS-3

Note:

• This change was first reviewed and merged in fix: added logout user before sso pipeline starts edx/auth-backends#2.
• These changes were tested on the 2U stage environment, but testing in 2U prod against multiple services will be simpler when this has merged in openedx.
• This change solves more issues at the root, and once proven out and the toggle is removed, it will allow for clean-up/removal of earlier PRs like fix: enhance get_user_if_exists pipeline function with debugging capabilities #390, because a username mismatch will no longer be possible.

[feanil]

@Akanshu-2u changes look good, can you bump the version of the library so that we can do a release once we merge this?

[Akanshu-2u]

@Akanshu-2u changes look good, can you bump the version of the library so that we can do a release once we merge this?

Addressed. Added version bump of the library. Thank you.

[robrap]

Thanks @feanil.

[robrap]

@feanil: We'll see if we can get this fully tested and rolled out (on by default) for Ulmo on Oct 9.
FYI: @Akanshu-2u