Update to support Django 4

[etanttila]

Description

What?

Remove features deprecated and removed in Django version 4.

Why?

Django 4.2 (LTS) was released in April 2023. Django v3.2 reaches end of life in April 2024. At least MOOC-Jutut is dependent on this library, so in order for it to be updated to use Django 4.2, this needs to also support ir.

How?

I went through the release notes for Django 4.0, 4.1 and 4.2 and checked which deprecated and removed features appear in the codebase, and removed/updated those. Edited the requirementes file to allow Django version 4 to be used.

Fixes #2

Testing

Remember to add or update unit tests for new features and changes.

• How to test your changes in A-plus
• How to test accessibility

What type of test did you run?

• Accessibility test using the WAVE extension.
• Django unit tests.
• Selenium tests.
• Other test. (Add a description below)
• Manual testing.

Tested normal use of Jutut, which worked (sending feedback, responding to feedback; updating student tags; adding, editing, deleting feedback tags; adding and removing feedback tags to feedback; filtering feedback; different pages on the site).

Did you test the changes in

• Chrome
• Firefox
• This pull request cannot be tested in the browser.

Think of what is affected by these changes and could become broken

Translation

• Did you modify or add new strings in the user interface? (Read about how to create translation)

Programming style

• Did you follow our style guides?
• Did you use Python type hinting in all functions that you added or edited? (type hints for function parameters and return values)

Have you updated the README or other relevant documentation?

• documents inside the doc directory.
• README.md.
• Aplus Manual.
• Other documentation (mention below which documentation).

Is it Done?

• Reviewer has finished the code review
• After the review, the developer has made changes accordingly
• Customer/Teacher has accepted the implementation of the feature

Clean up your git commit history before submitting the pull request!

[markkuriekkinen]

Looks good!

[markkuriekkinen]

We could jump to version 1.6 since we are targeting an all new Django LTS version.