Split requirements for building RTD docs

[dojutsu-user]

We want to have a separate file requirements/docs.txt which contains the dependencies required for building RTD docs only.

Example: If a virtual environment is created and packges are installed from requirements/docs.txt only and then if the docs are build (located at readthedocs/docs/) with make html command, It should succeed.

This is discussed in PR #5100

[dojutsu-user]

@humitos
I researched on this issue a bit.
We need to take some design decisions on this.
Turns out that these two lines will go through all the requirements mentioned in INSTALLED_APPS and will raise an error if the app is not found.
https://github.com/rtfd/readthedocs.org/blob/86bfdffaee2a6a5143f6c7c75af2600817101ce1/docs/conf.py#L18-L19
That's the reason, make html command raises ModuleNotFoundError error for the apps starting with celery, dj_pagination, taggit and so on.
Also if these two lines are commented out, this line
https://github.com/rtfd/readthedocs.org/blob/86bfdffaee2a6a5143f6c7c75af2600817101ce1/docs/doc_extensions.py#L18
raises an django.core.exceptions.AppRegistryNotReady error which is legit as django.setup() is required to load the apps.

[dojutsu-user]

Also, doc_extensions.py uses some setting variables from settings which are not accessible without django.setup()

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This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[dojutsu-user]

This is still valid I think.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[dojutsu-user]

@humitos
Is this actionable or should we close it for now?

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.