Update the sample to latest MSAL and public client redirect URI

[jmprieur]

The sample:

• does not use the latest MSAL.NET
• still uses the urn: redirect URI

We should update it.

cc: @aiwangmicrosoft @jennyf19

[jennyf19]

@aiwangmicrosoft status on this?

[aiwangmicrosoft]

Haven't started and don't plan to this week, is this hi pri?

[jennyf19]

@aiwangmicrosoft Updating the URI should be a string replacement and then testing. Should be done sooner than later. Or assign to someone else if you don't have time.