Cleanup unused code (Azure#47632)

Author: christothes

sdk/identity/Azure.Identity/src/AppServiceManagedIdentitySource.cs

@@ -16,22 +16,12 @@ internal class Constants
         // TODO: Currently this is piggybacking off the Azure CLI client ID, but needs to be switched once the Developer Sign On application is available
         public const string DeveloperSignOnClientId = "04b07795-8ddb-461a-bbee-02f9e1bf7b46";
 
-        public static string SharedTokenCacheFilePath { get { return Path.Combine(DefaultMsalTokenCacheDirectory, DefaultMsalTokenCacheName); } }
-
-        public const int SharedTokenCacheAccessRetryCount = 100;
-
-        public static readonly TimeSpan SharedTokenCacheAccessRetryDelay = TimeSpan.FromMilliseconds(600);
-
         public const string DefaultRedirectUrl = "http://localhost";
 
         public static readonly string DefaultMsalTokenCacheDirectory = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), ".IdentityService");
 
         public const string DefaultMsalTokenCacheKeychainService = "Microsoft.Developer.IdentityService";
 
-        public const string DefaultMsalTokenCacheKeychainAccount = "MSALCache";
-
-        public const string DefaultMsalTokenCacheKeyringLabel = "MSALCache";
-
         public const string DefaultMsalTokenCacheKeyringSchema = "msal.cache";
 
         public const string DefaultMsalTokenCacheKeyringCollection = "default";