[C# 10 diagnostics] Interpolated string handlers, interpolated strings

[BillWagner]

Describe the issue or suggestion

Create a new page for interpolated string handlers.

From C# 10, this includes the following errors:

• CS8941
• CS8942
• CS8946
• CS8947
• CS8953
• CS8976

In addition, search for other diagnostics related to interpolated string handlers.

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Associated WorkItem - 550648