Microsoft.UI.Xaml v2.7.1-prerelease.211026002

https://www.nuget.org/packages/Microsoft.UI.Xaml/2.7.1-prerelease.211026002

Changes:

• 8f9b626 Move IPopup4 to Private namespace
• db58b12 bump version to 2.7.1
• 379b964 Fix #5768 (#6063)
• 61d5e74 Fix color picker element tab order in horizonal mode. (#5939)
• 803f334 Fix the sliders in a horizontally oriented color picker going the incorrect direction with arrow keys. (#5934)
• 50e45a2 Fix InfoBadge default high contrast background. (#5899)
• ba8fd80 Enable Arm builds of the NugetPackageTestApp (#5982)
• da05255 Cherry-pick fixes to 2.7 release branch for servicing (#6134) [ #6014, #6033, #6121, #6131 ]
• dc21a21 Update intellisense files