Add docs for IDE0306

[gewarren]

Fixes #45100

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Internal previews

📄 File	🔗 Preview link
docs/fundamentals/code-analysis/style-rules/ide0300.md	Use collection expression for array (IDE0300)
docs/fundamentals/code-analysis/style-rules/ide0301.md	"IDE0301: Use collection expression for empty"
docs/fundamentals/code-analysis/style-rules/ide0303.md	Use collection expression for Create() (IDE0303)
docs/fundamentals/code-analysis/style-rules/ide0304.md	docs/fundamentals/code-analysis/style-rules/ide0304
docs/fundamentals/code-analysis/style-rules/ide0305.md	Use collection expression for fluent (IDE0305)
docs/fundamentals/code-analysis/style-rules/ide0306.md	"IDE0306: Use collection expression for new"
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

[BillWagner]

This looks great @gewarren

I had one question, which is worth checking with Cyrus to see if my thoughts are correct.

Then, let's