Formatting guidelines: clarify how empty class, struct and interface declarations should be formatted

[Shuenhoy]

How empty class, struct and interface declarations should be formatted is missing in current docs.
I would prefer a one-line style:

type AnEmptyClass = class end

instead of

type AnEmptyClass =
    class
    end

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Document Details

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• ID: 8c09996f-24ac-cf39-ef43-d7909cbc2b89
• Version Independent ID: 1efdd523-8552-6421-e149-74f76826ef8f
• Content: F# code formatting guidelines
• Content Source: docs/fsharp/style-guide/formatting.md
• Product: dotnet-fsharp
• GitHub Login: @cartermp
• Microsoft Alias: dotnetcontent

[BillWagner]

@dsyme which style do you prefer?

[dsyme]

The first. cc @nojaf for comment

[nojaf]

This works for me, I don't see any real problems.
One edge cases that might be reported in Fantomas would be the following:

module A =
    module B =
        module C =
            module D =
                module E =
                    type SuperLooooooooooooonnnnggggggggggTypeNameeeeeeeeeeeeeeeeForNooooooooooGoooooooooodReason = class end

In that scenario, this would cross the max_line_length.
Highly unlikely to appear in the wild I think.
@dsyme perhaps this should be mentioned that regardless of the chosen page width, it should always be = class end on the same line.