Clarify a list of supported signed commits types
What does this MR do and why?
Contributes to #450519 (closed)
Problem
In our documentation we mention that only GPG signed commits can be rejected by push rules. However, it's not true. This setting applies to all supported signed commit types: SSH, GPG and X.509.
Solution
Update the documentation to clarify that.
Edited by Vasilii Iakliushin