[v2] Use higher key size for TestSha256RSADigestValidator

[fossdd]

Issue #, if available:

Description of changes:

cryptography 43.0.0 requires bumped the minimum key size to 1024.

Since rsa.generate_private_key() is only used in this test, this is fine.

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[kdaily]

Hi @fossdd! Thanks for opening this. I came across this separately and bumped up the keysize to 2048 (#8903). Closing this out for now. We are still working towards moving the pin for cryptography.

[fossdd]

I came across this separately and bumped up the keysize to 2048.

That's great! Thanks!

We are still working towards moving the pin for cryptography.

Yeah, downstream at Alpine (and other distros) we mostly use latest version of libraries and notice changes like that early. But I don't mind fixing them and upstream them, if that makes life easier (and hopefully doesn't duplicate work).