Rename Sticky Activities sample

[lorensr]

To match temporalio/samples-typescript#268

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[cretz]

One minor actionable comment, up to you if you want to fix now or not

[cretz]

LGTM. You may also want to do this to https://github.com/temporalio/samples-dotnet/tree/main/src/ActivityStickyQueues and https://github.com/temporalio/samples-go/tree/main/activities-sticky-queues or at least open the issues.

You can feel free to merge this or I can.

[cretz]

@lorensr - Just merged #78 which conflicts here. Feel free to fix and merge.