Describe how new Code Style and Docstring Style options work in Spyder 4

[CAM-Gerlach]

Issue Description

Per the discussion in spyder-ide/spyder#9231 and specifically @ccordoba12 's request, we should describe how to use the Code and Doc Style settings in Spyder 4's preferences, particularly the interaction between the "Show" and "Ignore" fields. This would probably be best worked into an expanded Editor article, specifically a discussion on the various LSP-provided features the editor offers (Code Analysis, Hints, Calltips, Completion, etc.); otherwise; it would be part of a broader article/docs section that discusses Spyder's preferences in more detail (which I hope to add at some point).

[juanis2112]

Adding this as editor feature

[CAM-Gerlach]

@hyounes4560 if you have time, we could work this in to an expanded discussion of the Code/docstring style options in the "Code Style" section of the Editor doc, though I don't think we should block your initial PR on this—it can be added later, and I can take care of it if necessary, since its a more advanced feature.

[hyounes4560]

@CAM-Gerlach Could you please add more info about this?

[CAM-Gerlach]

Sure. Basically, we want to describe how the Show and Ignore fields work in the Code Style and Docstyle tabs under the Completion and Linting Preferences pane, i.e. as Daniel describes in his comment I linked above: spyder-ide/spyder#9231 (comment) However, upon closer inspection, this is fairly minor and can be added later, either by you, me or somewhere else, since it is a pretty advanced feature. So, I wouldn't worry about this for #331 unless you really want to, in which case I'm happy to help guide you further.