Remove excessive Grid API comment

[jfversluis]

Description of Change

The current example for the Grid API docs is a bit much and can be annoying to work with when inside of Visual Studio. See the screenshot underneath taken from: https://developercommunity.visualstudio.com/t/excessive-examples-in-comment-popup/10638087

This PR removes the example reducing the API doc to an acceptable level.

[axa88]

wonderful. No code samples in comments probably should be added to the project coding styles.
For by every measure measure what was done to Grid should be applied to every other type that saw fit to place code samples, let alone excessive code samples in its comment.
See StackLayout

I digress #24114

There maybe others though, even what's in Label is uselessly verbose...