Config file: system_site_packages overwritten from project's setting

[humitos]

I created a test case to demostrate what was reported in the issue. Summarizing,
if the project uses a config file and does not define python.system_packages
but has Project.use_system_packages=True the config option is True which is
wrong. When a config file is used, settings at Project level should be ignored
as this messages from "Advanced settings" states:

These settings can be configured using a configuration file. That's the
recommended way to set up your project. Settings listed here are ignored when
using a configuration file.

Reference #8782

[humitos]

If I understand correctly, we are defining the defaults with values coming from the project object itself, which I think it's wrong:

readthedocs.org/readthedocs/doc_builder/config.py

Line 43 in 34ff065

'use_system_packages': project.use_system_packages,

I think all those defaults should be the defaults we have documented in https://docs.readthedocs.io/en/stable/config-file/v2.html and not the values defined at project object (from the Admin). @stsewd am I right?

[stsewd]

@humitos most of those default values are used in the v1 config file. But this one should always default to false

readthedocs.org/readthedocs/config/config.py

Lines 940 to 949 in c4a61c9

	with self.catch_validation_error('python.system_packages'):
	system_packages = self.defaults.get(
	'use_system_packages',
	False,
	)
	system_packages = self.pop_config(
	'python.system_packages',
	system_packages,
	)
	python['use_system_site_packages'] = validate_bool(system_packages)

[humitos]

@stsewd I don't follow you. The code that I linked seems to be used by config v2 as well, right? If we need different default values for v1 and v2 we should reflect that creating different dictionaries, right?

[stsewd]

@humitos that use_system_packages from v2 shouldn't use self.defaults, it should always default to false.

[humitos]

@stsewd I pushed a commit with the change. Is it correct? I assume my test should pass now.