Add Nested annotation in Demo where it's missing

[IlyasYOY]

Added Nested annotations where they seemed to be missing. Ran tests to be sure the fix didn't introduced failing tests.

I was going through demo classes and found some nested tests not marked Nested. I thought that not using Nested annotation might get stale.

open problems:

• There are still some tests that are didn't manage to get running.
• I didn't include myself in Contributing, because change is really minor.
• Those tests might have been better off w/o Nested.
• I think that we also missing Test here.

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[Michael1993]

This is a great catch. We really don't pay enough attention to the demo tests. 😅

I don't think there are contributions that are 'too small', so if you would like to add yourself as a contributor feel free to do so!

[IlyasYOY]

I don't think there are contributions that are 'too small', so if you would like to add yourself as a contributor feel free to do so!

Added myself as contributor. I'll try to help with more issues.

Thank you for this library!

[nipafx]

Thank you @IlyasYOY for the PR, this is really neat! The demos need more attention and we appreciated you gave it some. ❤️

I added some local changes, but it looks like I can't push to your branch. Maybe because it's the main branch? In the future, please create a new branch for your contributions - see the contribution guide for details.

I will open a new PR with these changes, so I can add mine and merge it. Thanks again! 😃