Why do I get this message?
The authenticity of host 'gitlab.com (35.231.145.151)' can't be established.
I can't find that IP on https://docs.gitlab.com/ee/user/gitlab_com/
Why do I get this message?
The authenticity of host 'gitlab.com (35.231.145.151)' can't be established.
I can't find that IP on https://docs.gitlab.com/ee/user/gitlab_com/
I can't find that IP
The page you mention only includes the IP for GItLab pages.
It does include the SSH host keys fingerprints though.
So do type 'yes', to accept the authenticity of gitlab.com, then fo to your ~/.ssh/known_hosts file, and do check it includes one of the SSH host keys fingerprints listed in the documentation.