[Demo App] Update Label upon successful scan

[LanceMcCarthy]

The demo give the impression to some developers that a scan was not successful because the "Top Text..." label content doesn't update.

So I just added an x:Name to the label and update the value after a scan.

[LanceMcCarthy]

Looking at the failed build output, I have a couple quick tips:

Error

The error is "Unspecified error", so I'm not much help there without digging deeper.

Issue

I can help with this one as I've had to update all my different libraries to use the new output variables approach.

Warning: The set-output command is deprecated and will be disabled soon

OLD:

$buildDay = Get-Date -Format "yyyy.Mdd"
$runNumber = "$env:GITHUB_RUN_NUMBER"
$ver = $buildDay + "." + $runNumber + ".0"

# deprecated way
echo "::set-output name=APP_VERSION::$ver"

NEW:

$buildDay = Get-Date -Format "yyyy.Mdd"
$runNumber = "$env:GITHUB_RUN_NUMBER"
$ver = $buildDay + "." + $runNumber + ".0"

#new way
echo "APP_VERSION=$ver" >> $GITHUB_OUTPUT