doc(active_record): adding more examples about scope control

[JohnAnon9771]

Motivation / Background

In the rails contributors discord, there was a discussion in the past about a Rails behavior that is somewhat unknown to Rails newbies (I am included in that list) where it showed that Rails can identify which relationship you define according to the scope of the model.

I'm opening this PR for opinions on how this can be documented, as it seems to be something very interesting about Rails and which is only noticed if you have the correct intuition that Rails can do this.

rails/activerecord/lib/active_record/inheritance.rb

Lines 241 to 244 in c9cdd80

	# Build a list of candidates to search for
	candidates = []
	name.scan(/::|$/) { candidates.unshift "#{$`}::#{type_name}" }
	candidates << type_name

Checklist

Before submitting the PR make sure the following are checked:

• This Pull Request is related to one change. Changes that are unrelated should be opened in separate PRs.
• Commit message has a detailed description of what changed and why. If this PR fixes a related issue include it in the commit message. Ex: [Fix #issue-number]
• Tests are added or updated if you fix a bug or add a feature.
• CHANGELOG files are updated for the changed libraries if there is a behavior change or additional feature. Minor bug fixes and documentation changes should not be included.

[JohnAnon9771]

Thank you very much @p8 for the feedback, I have already made the suggested changes.

[p8]

A small change to maybe make things a bit clearer what the advantage is:

Suggested change

	This will work fine, because both the `Supplier` and the `Account` class are defined within the same scope (`MyApplication::Business`). This organization allows structuring models into folders based on their scope:
	This will work fine, because both the `Supplier` and the `Account` class are defined within the same scope (`MyApplication::Business`). This organization allows structuring models into folders based on their scope, without having to explicitly add the scope to every association:

[JohnAnon9771]

Done! 😄

[p8]

Thanks @JohnAnon9771 !