Fix corrupt certificate test

[rturner3]

The error message returned by the x509 package in the test case changed with a newer version of Go. Update the test to look for the new error message.

missed something.

[azdagron]

So, as it stands, this library is set to a go1.13 minimum and that is the version we run our tests with. Independent of the minimum version we support, we should probably be running our tests against each version of go.

In either case, unless we pull up our minimum supported version, this test should still continue to function with go1.13. This might require us to use build tags to change up which error string we test here.

[rturner3]

So, as it stands, this library is set to a go1.13 minimum and that is the version we run our tests with. Independent of the minimum version we support, we should probably be running our tests against each version of go.

In either case, unless we pull up our minimum supported version, this test should still continue to function with go1.13. This might require us to use build tags to change up which error string we test here.

That makes sense. I agree that there is some missing infrastructure before we can really take a change like this. I've filed #206 to track that effort.

I will go ahead and close out this PR for now. I've referenced it in the issue I created so this doesn't get lost.