Add example for BlobEncoder.MethodSignature

[MSDN-WhiteKnight]

Add examples that generate different shapes of method signatures with BlobEncoder.

Note: if you want to verify that encoded signatures are valid, you can use this sample which does similar things, but produce a complete assembly that could be inspected with ildasm. I'm not adding a complete sample here, because MetadataBuilder already has it.

[ghost]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[opbld34]

Docs Build status updates of commit 8638262:

✅ Validation status: passed

File	Status	Preview URL	Details
snippets/csharp/System.Reflection.Metadata.Ecma335/BlobEncoder/MethodSignature/MethodSignatureSnippets.cs	✅Succeeded	View
snippets/csharp/System.Reflection.Metadata.Ecma335/BlobEncoder/MethodSignature/MethodSignatureSnippets.csproj	✅Succeeded
snippets/csharp/System.Reflection.Metadata.Ecma335/BlobEncoder/MethodSignature/Program.cs	✅Succeeded
xml/System.Reflection.Metadata.Ecma335/BlobEncoder.xml	✅Succeeded	View

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Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

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[opbld30]

Docs Build status updates of commit 5f5b40c:

✅ Validation status: passed

File	Status	Preview URL	Details
snippets/csharp/System.Reflection.Metadata.Ecma335/BlobEncoder/MethodSignature/MethodSignatureSnippets.cs	✅Succeeded	View
snippets/csharp/System.Reflection.Metadata.Ecma335/BlobEncoder/MethodSignature/MethodSignatureSnippets.csproj	✅Succeeded
snippets/csharp/System.Reflection.Metadata.Ecma335/BlobEncoder/MethodSignature/Program.cs	✅Succeeded
xml/System.Reflection.Metadata.Ecma335/BlobEncoder.xml	✅Succeeded	View

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

• Try searching the docs.microsoft.com contributor guides
• Post your question in the Docs support channel

[buyaa-n]

LGTM, thanks!