fix cert uploading issues

[lil131]

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[lil131]

1. fixing the reported issue: Certificate upload fails via cli but works via portal
2. fixing the bug where replacing invalid characters in cert names failed
3. removing the test case for .pem cert uploading for now, as the api doesn't support .pem certs yet, and a private key validation was added to the api recently which will lead to the "Certificate must contain one private key." error for .pem certs.

[StrawnSC]

Looks like there's a small merge conflict that needs to be fixed before we can merge

[StrawnSC]

Also, @lil131 can you link the GitHub issue(s) that are related to this fix?