### What does this PR do?
there was a regression in 1.2.5 where it stopped supporting lowercase
veriants of the crypto keys. This broke the `mailauth` lib and proabibly
many more.
simple code:
```ts
import { sign, constants } from 'crypto';
const DUMMY_PRIVATE_KEY = `-----BEGIN PRIVATE KEY-----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\r\nK3P7zdJ30gregvjI\r\n-----END PRIVATE KEY-----`;
sign('rsa-sha256', Buffer.from('message'), {
key: DUMMY_PRIVATE_KEY,
padding: constants.RSA_PKCS1_PSS_PADDING,
});
// would throw invalid digest
```
### How did you verify your code works?
made test
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
