Windowscommunitytoolkit: SampleApp doesn't show custom protocols in links

[michael-hawker]

Describe the bug

If you use a custom protocol link like [this one](uwpct://Controls?sample=AdaptiveGridView) like we do in the new documentation to open the sample app. The MarkdownTextBlock won't convert it to a hyperlink (apparently neither does GitHub).

Steps to Reproduce

Steps to reproduce the behavior:

1. Go to AdaptiveGridView sample
2. Click on Documentation
3. Scroll down to 'Sample Project' section
4. See error

Expected behavior

Expect to see a hyperlink, would still expect developer to have to process and act on link event like they do for web urls.

Screenshots

Environment

master branch

[avknaidu]

@michael-hawker i added a property for this called SchemeList. If you add uwpct to SchemeList Property, it will render correctly.

See Below.

[michael-hawker]

Thanks @avknaidu! Helps if I read our own docs I guess. 😋

I thought we had fixed this before, we just forgot to add to the SampleApp. I'll do this now!