test-with-sslib-main fails

[jku]

Currently all CI runs fail the test-with-sslib-main test:
KeyMismatchError("CryptoSigner private key does not match public key")

This is a new check that was added in securesystemslib secure-systems-lab/securesystemslib#1196 -- I suspect we just use sketchy test keys but this needs to be investigated.

[jku]

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ERROR: setUpClass (tests.test_trusted_metadata_set.TestTrustedMetadataSet)
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Traceback (most recent call last):
  File "/home/runner/work/python-tuf/python-tuf/tests/test_trusted_metadata_set.py", line 98, in setUpClass
    cls.keystore[role] = Signer.from_priv_key_uri(uri, key)
                         ~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^
  File "/home/runner/work/python-tuf/python-tuf/.tox/with-sslib-main/lib/python3.14/site-packages/securesystemslib/signer/_signer.py", line 111, in from_priv_key_uri
    return signer.from_priv_key_uri(priv_key_uri, public_key, secrets_handler)  # type: ignore
           ~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/runner/work/python-tuf/python-tuf/.tox/with-sslib-main/lib/python3.14/site-packages/securesystemslib/signer/_crypto_signer.py", line 323, in from_priv_key_uri
    return CryptoSigner(private_key, public_key)
  File "/home/runner/work/python-tuf/python-tuf/.tox/with-sslib-main/lib/python3.14/site-packages/securesystemslib/signer/_crypto_signer.py", line 249, in __init__
    raise KeyMismatchError("CryptoSigner private key does not match public key")
securesystemslib.exceptions.KeyMismatchError: CryptoSigner private key does not match public key

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ERROR: test_updating_root (tests.test_updater_ng.TestUpdater.test_updating_root)
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Traceback (most recent call last):
  File "/home/runner/work/python-tuf/python-tuf/tests/test_updater_ng.py", line 296, in test_updating_root
    self._modify_repository_root(lambda _: None, bump_version=True)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/runner/work/python-tuf/python-tuf/tests/test_updater_ng.py", line 143, in _modify_repository_root
    signer = Signer.from_priv_key_uri(uri, key)
  File "/home/runner/work/python-tuf/python-tuf/.tox/with-sslib-main/lib/python3.14/site-packages/securesystemslib/signer/_signer.py", line 111, in from_priv_key_uri
    return signer.from_priv_key_uri(priv_key_uri, public_key, secrets_handler)  # type: ignore
           ~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/runner/work/python-tuf/python-tuf/.tox/with-sslib-main/lib/python3.14/site-packages/securesystemslib/signer/_crypto_signer.py", line 323, in from_priv_key_uri
    return CryptoSigner(private_key, public_key)
  File "/home/runner/work/python-tuf/python-tuf/.tox/with-sslib-main/lib/python3.14/site-packages/securesystemslib/signer/_crypto_signer.py", line 249, in __init__
    raise KeyMismatchError("CryptoSigner private key does not match public key")
securesystemslib.exceptions.KeyMismatchError: CryptoSigner private key does not match public key

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Ran 176 tests in 5.451s

[jku]

secure-systems-lab/securesystemslib#1197