Ensure samesite=none logged_in cookies are deleted

[bryanlandia]

Change description

Fix an upstream issue with Open edX < Maple / Django < 3.2.7 causing samesite cookie deletion to fail.

Fixes ENG-53 Patch delete_logged_in_cookies to bypass Django < 3.2.7 (Maple+) delete_cookie. It relies on prefix of __SECURE to determine secure cookies, so we have to use set_cookie with an expired date. Note this will still work with Session cookie domain middleware. Adapted from https://discuss.overhang.io/t/logged-in-cookies-not-deleted-on-logout-over-https-not-reproducible-on-edx-org/1011/6

Type of change

• [x] Bug fix (fixes an issue)
• [ ] New feature (adds functionality)

Related issues

https://appsembler.atlassian.net/browse/ENG-53

Checklists

Development

• [x] Lint rules pass locally
• [x] Application changes have been tested thoroughly
• [x] Automated tests covering modified code pass

Security

• [x] Security impact of change has been considered
• [x] Code follows company security practices and guidelines

Code review

• [x] Pull request has a descriptive title and context useful to a reviewer. Screenshots or screencasts are attached as necessary
• [x] "Ready for review" label attached and reviewers assigned
• [ ] Changes have been reviewed by at least one other contributor
• [x] Pull request linked to task tracker where applicable

[github-actions[bot]]

Checking git merge conflicts against https://github.com/edx/edx-platform.git

Comparing with	open-release/nutmeg.master
Benchmark conflicts with main	292
Current conflicts	293
Summary	Adds 1 new conflicts. How can we do better?

New conflicting files with 'open-release/nutmeg.master'

``` openedx/core/djangoapps/user_authn/cookies.py ```

Comparing with	master
Benchmark conflicts with main	300
Current conflicts	301
Summary	Adds 1 new conflicts. How can we do better?

New conflicting files with 'master'

``` openedx/core/djangoapps/user_authn/cookies.py ```

[github-actions[bot]]

Checking git merge conflicts against https://github.com/edx/edx-platform.git

Comparing with	open-release/nutmeg.master
Benchmark conflicts with main	292
Current conflicts	293
Summary	Adds 1 new conflicts. How can we do better?

New conflicting files with 'open-release/nutmeg.master'

``` openedx/core/djangoapps/user_authn/cookies.py ```

Comparing with	master
Benchmark conflicts with main	300
Current conflicts	301
Summary	Adds 1 new conflicts. How can we do better?

New conflicting files with 'master'

``` openedx/core/djangoapps/user_authn/cookies.py ```

[github-actions[bot]]

Checking git merge conflicts against https://github.com/edx/edx-platform.git

Comparing with	open-release/nutmeg.master
Benchmark conflicts with main	292
Current conflicts	293
Summary	Adds 1 new conflicts. How can we do better?

New conflicting files with 'open-release/nutmeg.master'

``` openedx/core/djangoapps/user_authn/cookies.py ```

Comparing with	master
Benchmark conflicts with main	300
Current conflicts	301
Summary	Adds 1 new conflicts. How can we do better?

New conflicting files with 'master'

``` openedx/core/djangoapps/user_authn/cookies.py ```

[github-actions[bot]]

Checking git merge conflicts against https://github.com/edx/edx-platform.git

Comparing with	open-release/nutmeg.master
Benchmark conflicts with main	292
Current conflicts	293
Summary	Adds 1 new conflicts. How can we do better?

New conflicting files with 'open-release/nutmeg.master'

``` openedx/core/djangoapps/user_authn/cookies.py ```

Comparing with	master
Benchmark conflicts with main	300
Current conflicts	301
Summary	Adds 1 new conflicts. How can we do better?

New conflicting files with 'master'

``` openedx/core/djangoapps/user_authn/cookies.py ```

[github-actions[bot]]

Checking git merge conflicts against https://github.com/edx/edx-platform.git

Comparing with	open-release/nutmeg.master
Benchmark conflicts with main	292
Current conflicts	293
Summary	Adds 1 new conflicts. How can we do better?

New conflicting files with 'open-release/nutmeg.master'

``` openedx/core/djangoapps/user_authn/cookies.py ```

Comparing with	master
Benchmark conflicts with main	300
Current conflicts	301
Summary	Adds 1 new conflicts. How can we do better?

New conflicting files with 'master'

``` openedx/core/djangoapps/user_authn/cookies.py ```

[bryanlandia]

I have this cherrypicked to PSU's branch and it's working well.