Make semicolons optional between attributes when on separate lines

[edgarfgp]

Description

This PR makes semicolons optional between attributes when they appear on separate lines. This improves readability and reduces visual noise in multi-line attribute declarations.

Fixes # (issue, if applicable) There is an issue somewhere but could not find it.

Before this change, semicolons were required between attributes even when on separate lines:

[<Obsolete("Message 1"); 
  Obsolete("Message 2")>]

After this change, both forms are valid:

// With semicolons (existing syntax)
[<Obsolete("Message 1"); 
  Obsolete("Message 2")>]

// Without semicolons when on separate lines (new syntax)
[<Obsolete("Message 1")
  Obsolete("Message 2")>]

// Same line still requires semicolons
[<Obsolete("Message 1"); Obsolete("Message 2")>]

Checklist

• Test cases added
• Performance benchmarks added in case of performance changes
• Release notes entry updated

[github-actions]

❗ Release notes required

@edgarfgp,

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Change path	Release notes path	Description
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[brianrourkeboll]

Is it worth having a test where the second one is not indented far enough? Would it be considered offsides? What about a mixture of semicolons and newlines?

[auduchinok]

@edgarfgp This should probably follow the logic in LexFilter for sequential expressions. Simply allowing spaces is likely to change parsing of attributes [<Attr Const>] which we don't want.

[vzarytovskii]

This will also require an rfc, since it's a change to how things are lexed.