Typo "Azure function"→"Azure Function"

[hyoshioka0128]

Purpose

• Typo "Azure function"→"Azure Function"
  https://docs.microsoft.com/en-us/samples/azure-samples/event-grid-dotnet-handle-deadlettered-events/event-grid-dotnet-handle-deadlettered-events/

Does this introduce a breaking change?

[ ] Yes
[x] No

Pull Request Type

What kind of change does this Pull Request introduce?

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

[hyoshioka0128]

@TinaMcN Could you please explain a bit more about the reason of PR not being built? Thanks.