Merge pull request #24 from manu-thomas-87/master

Changing the exception type

Author: dazinator

src/AspNetCore.LegacyAuthCookieCompat/LegacyFormsAuthenticationTicketEncryptor.cs

@@ -180,7 +180,7 @@ private byte[] Decrypt(byte[] cookieBlob, HashProvider hasher, bool isHashAppend
                 if (cookieBlob == null)
                 {
                     // signature verification failed
-                    throw new Exception("Signature verification failed");
+                    throw new CryptographicException("Signature verification failed");
                 }
             }