[Bug] client_credentials throttling error is not easy to understand

[bgavrilMS]

msal 4.35.1

If app developers mis-configure their app with regards to token caching (i.e. no token cache), AAD replies with HTTP status 429 and a Retry-After header.

Expected: the exception should make the potential root cause clear - throttling because lack of app cache - and provide an https://aka.ms/ link

Actual: The application developer sees the following exception:

Microsoft.Identity.Client.MsalThrottledServiceException: An error response was returned by the OAuth2 server, but it could not be parsed. Please inspect the exception properties for details.

StatusCode: 429
ResponseBody: Too Many Requests
Headers: Retry-After: 60