Add IDE0320 and IDE0330

[gewarren]

Fixes #42105 (IDE0320)
Contributes to #43163 (IDE0330)

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Internal previews

📄 File	🔗 Preview link
docs/fundamentals/code-analysis/style-rules/ide0250.md	Struct can be made 'readonly' (IDE0250)
docs/fundamentals/code-analysis/style-rules/ide0251.md	"IDE0251: Member can be made 'readonly'"
docs/fundamentals/code-analysis/style-rules/ide0320.md	Make anonymous function static (IDE0320)
docs/fundamentals/code-analysis/style-rules/ide0330.md	docs/fundamentals/code-analysis/style-rules/ide0330
docs/fundamentals/code-analysis/style-rules/index.md	Code-style rules
docs/fundamentals/code-analysis/style-rules/language-rules.md	Language and unnecessary rules
docs/navigate/tools-diagnostics/toc.yml	docs/navigate/tools-diagnostics/toc

[gewarren]

@CyrusNajmabadi FYI I wasn't able to get these to fire for a command-line build or even in the Error List in VS. I only saw them under the light bulb in the IDE. Is that expected?

[CyrusNajmabadi]

@CyrusNajmabadi FYI I wasn't able to get these to fire for a command-line build

I have no idea how that works. Tagging @mavasani or @sharwell who know better what controls that :)

[BillWagner]

These all look good. Let's