Fix Pivot control's description

[AndrewKeepCoding]

Description

Change Pivot control's description back to plain text since html tags are not supported here.

Motivation and Context

Closes #1504

How Has This Been Tested?

Run the app and confirmed that the Pivot description doesn't have html tags.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

[marcelwgn]

Thank you for fixing this @AndrewKeepCoding

[Jay-o-Way]

@marcelwgn please link the issue, and look into the fact if it's really deprecated or not. I don't believe it is.

[marcelwgn]

Thanks for mentioning the issue @Jay-o-Way. Pivot is deprecated as indicated here and you should not use it anymore: https://learn.microsoft.com/en-us/windows/apps/design/controls/pivot#is-this-the-right-control

[Jay-o-Way]

Yeah, but, what if that doc is outdated? It hasn't been changed in "almost" a year, roughly around the time things were not definitive...

[marcelwgn]

Even if we assume the docs are outdated, I find it hard to believe that the sentence "Pivot is deprecated, please use SelectorBar" would be outdated given that Sidebar only was released with WinUI 1.5 a few weeks ago. Also see #1467 where this was added 2 weeks ago.

[karkarl]

/azp run

[karkarl]

Pivot was initially developed for Windows Phone, so a lot of functionality is specific to phone / touch scenarios. As such, we developed SelectorBar with a focus on perf, and will be recommending developers to use this control from now on.

So yes, Pivot is definitely being deprecated. :)