Changelog commit message always includes "[skip ci]"

[denisrevduplo]

When using "/update_changelog --pr_update_changelog.push_changelog_changes=true"
as part of a merge having "[skip ci] Update CHANGELOG.md" added as a commit in the merge branch can prevent actions from running. This prevents checks from passing.

Please make the commit message configurable, or add a way to disable adding [skip ci] every time in the commit msg.

[mrT23]

This was a direct request from the community, to avoid chain of infinite pipelines:

#857
#1185

You are welcome to open a PR making it configurable

[denisrevduplo]

To add more context, the way we prevent the infinite pipeline issue is we already have a path filter in our actions:

 paths-ignore:
      - '**.md'

[mrT23]

but that for specific file types and also requires an active change from the user.
[skip ci] is a general solution by pr-agent (that indeed may sometimes be unwanted)