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more minor fixes before I do larger fixes

Co-Authored-By: LogicalPhallacy <44458166+LogicalPhallacy@users.noreply.github.com>

Emby.Server.Implementations/Cryptography/CryptographyProvider.cs

@@ -96,7 +96,7 @@ namespace Emby.Server.Implementations.Cryptography
 
         public byte[] ComputeHash(string hashMethod, byte[] bytes)
         {
-            return ComputeHash(hashMethod, bytes, new byte[0]);
+            return ComputeHash(hashMethod, bytes, Array.Empty<byte>());
         }
 
         public byte[] ComputeHashWithDefaultMethod(byte[] bytes)

Emby.Server.Implementations/Library/DefaultAuthenticationProvider.cs

@@ -101,7 +101,7 @@ namespace Emby.Server.Implementations.Library
             if (!user.Password.Contains("$"))
             {
                 string hash = user.Password;
-                user.Password = String.Format("$SHA1${0}", hash);
+                user.Password = string.Format("$SHA1${0}", hash);
             }
             
             if (user.EasyPassword != null && !user.EasyPassword.Contains("$"))