fix AsyncResult used in AsyncResultOption.OfAsyncResult docs

[Larocceau]

code example used AsyncResult where it was supposed to be asyncResultOption

Proposed Changes

small fix in docs

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• [x ] Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

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• Build and tests pass locally
• I have added tests that prove my fix is effective or that my feature works (if appropriate)
• [x ] I have added necessary documentation (if appropriate)

Further comments

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[TheAngryByrd]

Thank you!