SampleTodoListTests

[joecare99]

What does the pull request do?

Add tests to the SampleTodoList-sample

Scope of this PR:

• fix or update to an existing sample
• add a new sample

What is the current behavior?

Sample is not tested

Checklist

If this is a new Sample

• Added a ReadMe-file
• Updated the landing page
• Consider submitting a PR to https://github.com/AvaloniaUI/avalonia-docs with a link to your sample in the related documentation page

In any case

• Spell-checking done
• Checked if all hyperlinks work
• Checked if all images are visible

Fixed issues

[timunie]

Hey @joecare99 ,

First of all, sorry for my very late response. I just didn't find the time to digg into it.
I really like your tests. However, I think for all samples this will be way to much and will probably confuse newbies. I will keep this PR and take your tests over to the advanced ToDo-List tutorial which I plan for October (🤞 hopefully). There a test is absolutely needed since it should cover a lot of "advanced" topics.

Again, thx for your contribution 💐