SS-887-custom-404-page

[churnikov]

Description

This draft PR add a template for django pages that are not found. For the pages, that won't be found on the k8s side, we need to a page on rancher side. @hamzaimran08 said, that he would provide more info on this the SS-887 task.

Checklist

If you're unsure about any of the items below, 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.

• [ x ] This pull request is against develop branch (not applicable for hotfixes)
• [ x ] I have included a link to the issue on GitHub or JIRA (if any)
• I have included migration files (if there are changes to the model classes)
• I have included, reviewed and executed tests (unit and end2end) to complement my changes
• I have updated the related documentation (if necessary)
• [ x ] I have added a reviewer for this pull request
• [ x ] I have added myself as an author for this pull request
• In the case I have modified settings.py, then I have also updated the studio-settings-configmap.yaml file in serve-charts

Further comments

Anything else you think we should know before merging your code!

[sandstromviktor]

LGMT lets merge