Good article. Some suggestions.
- As others pointed out, as SSH is asymmetrical, you need to explicitly say public key and private key.
- Some background on deploy key vs. regular ssh key, e.g. repo based vs. account based, as this may be none obvious to new users.
- Noting that ssh url should be used, not https one, as this is only apparent in the image.
- Prerequisites section, might want to mention the essential plugins needed to make this work, as not all Jenkins envs are alike. Most should have the credentials plugins installed, but may not be the case.