Error clone a second repo into config.yml using SSH

Build Environment
1

I’ve an automated tests repository and want to put that in a step of build, before to do a deploy.
But the clone repository steps fails (only last run step):

    automation:
        executor: web-app-executor
        steps:
          - add_ssh_keys:
              fingerprints:
                - '<my_fingerprint>'
          - run:
              name: Trust github ssh
              command: >-
                GIT_SSH_COMMAND='ssh -i ~/.ssh/id_rsa_myfingerprint'
                mkdir -p ~/.ssh
                echo 'github.com ssh-rsa <key>
                bitbucket.org ssh-rsa <key>
                ' >> ~/.ssh/known_hosts
          - run:
              name: Github host
              command: ssh-keyscan -p 443 ssh.github.com >> ~/.ssh/known_hosts
          - run:
              name: Clone automation repository
              command: git clone git@github.com:<Domain>/tests-cypress.git

Error:

#!/bin/bash -eo pipefail
git clone git@github.com:Onyo/tests-cypress.git
Cloning into 'tests-cypress'...
The authenticity of host 'github.com (140.82.113.3)' can't be established.
RSA key fingerprint is SHA256:<finger>.
2

Is the host (140.82.113.3) the same every time? Or is it changing? I’m wondering (and this is a stab in the dark?) if because it’s a round-robin for github.com that it’s causing issues? Or maybe that “ssh.github.com” isn’t added to the known_hosts?

Again, stabs in the dark…