test_import fails with ecdsa 0.19.0

[mweinelt]

Hi!

After updating ecdsa from 0.18.0 to 0.19.0 running the test suite errors out on test_import!

=================================== FAILURES ===================================
_________________________________ test_import __________________________________

ecdsa_signing_key_str = '-----BEGIN EC PRIVATE KEY-----\nMHcCAQEEIObr5IVtB+DQcn25+R9n4K/EyUUSbVvxIJY7WhVeELUuoAoGCCqGSM49\nAwEHoUQDQgAEOKyCQ9qH5U4lZcS0c5/LxIyKvOpKe0l3x4Eg5OgDbzezKNLRgT28\nfd4Fq3rU/1OQKmx6jSq0vTB5Ao/48m0iGg==\n-----END EC PRIVATE KEY-----\n'

    def test_import(ecdsa_signing_key_str: str):
        signer = RequestSigner.from_pem(ecdsa_signing_key_str)
        export = signer.export_signing_key()
    
>       assert ecdsa_signing_key_str == export
E       AssertionError: assert '-----BEGIN EC PRIVATE KEY-----\nMHcCAQEEIObr5IVtB+DQcn25+R9n4K/EyUUSbVvxIJY7WhVeELUuoAoGCCqGSM49\nAwEHoUQDQgAEOKyCQ9qH5U4lZcS0c5/LxIyKvOpKe0l3x4Eg5OgDbzezKNLRgT28\nfd4Fq3rU/1OQKmx6jSq0vTB5Ao/48m0iGg==\n-----END EC PRIVATE KEY-----\n' == '-----BEGIN EC PRIVATE KEY-----\nMHcCAQEEIObr5IVtB+DQcn25+R9n4K/EyUUSbVvxIJY7WhVeELUuoAoGCCqGSM49AwEHoUQDQgAE\nOKyCQ9qH5U4lZcS0c5/LxIyKvOpKe0l3x4Eg5OgDbzezKNLRgT28fd4Fq3rU/1OQKmx6jSq0vTB5\nAo/48m0iGg==\n-----END EC PRIVATE KEY-----\n'
E         
E           -----BEGIN EC PRIVATE KEY-----
E         - MHcCAQEEIObr5IVtB+DQcn25+R9n4K/EyUUSbVvxIJY7WhVeELUuoAoGCCqGSM49AwEHoUQDQgAE
E         ?                                                                 ------------
E         + MHcCAQEEIObr5IVtB+DQcn25+R9n4K/EyUUSbVvxIJY7WhVeELUuoAoGCCqGSM49
E         - OKyCQ9qH5U4lZcS0c5/LxIyKvOpKe0l3x4Eg5OgDbzezKNLRgT28fd4Fq3rU/1OQKmx6jSq0vTB5
E         - Ao/48m0iGg==
E         + AwEHoUQDQgAEOKyCQ9qH5U4lZcS0c5/LxIyKvOpKe0l3x4Eg5OgDbzezKNLRgT28
E         + fd4Fq3rU/1OQKmx6jSq0vTB5Ao/48m0iGg==
E           -----END EC PRIVATE KEY-----

tests/test_request_signer.py:103: AssertionError