[Key Vault] Prepare for mypy 1.13.0 (Azure#38935)

Author: mccoyp

sdk/keyvault/azure-keyvault-keys/azure/keyvault/keys/crypto/_internal/algorithms/ecdsa.py

@@ -2,9 +2,6 @@
 # Copyright (c) Microsoft Corporation.
 # Licensed under the MIT License.
 # ------------------------------------
-import abc
-import sys
-
 from cryptography.hazmat.primitives import hashes
 from cryptography.hazmat.primitives.asymmetric import ec
 from cryptography.hazmat.primitives.asymmetric import utils
@@ -13,13 +10,6 @@
 from ..transform import SignatureTransform
 from ..._enums import SignatureAlgorithm as KeyVaultSignatureAlgorithm
 
-if sys.version_info < (3, 3):
-    abstractproperty = abc.abstractproperty
-else:  # abc.abstractproperty is deprecated as of 3.3
-    import functools
-
-    abstractproperty = functools.partial(property, abc.abstractmethod)
-
 
 class _EcdsaSignatureTransform(SignatureTransform):
     def __init__(self, key, hash_algorithm):
@@ -39,10 +29,6 @@ class _Ecdsa(SignatureAlgorithm):
     def create_signature_transform(self, key):
         return _EcdsaSignatureTransform(key, self.default_hash_algorithm)
 
-    @abstractproperty
-    def coordinate_length(self):
-        pass
-
 
 class Ecdsa256(_Ecdsa):
     _name = KeyVaultSignatureAlgorithm.es256_k