Sanity check if the image name has a colon

[hoyhbx]

fix https://github.com/cockroachdb/cockroach-operator/issues/918

We fixed the issue by adding sanity check to examine whether a colon is contained in the image name in IsLoggingAPIEnabled function. If there is no colon in image name, we will not retrieve index 1 and will directly return false.

Checklist

• [ ] I have added these changes to the changelog (or it's not applicable).

[hoyhbx]

Thanks for your response. We have added a unit test in our latest commit.

[hoyhbx]

@pseudomuto Could you review this so that it can be merged? I think this is a pretty straight-forward fix