CI doesn't update to the appropriate revision

CI always runs with the latest revision (tip).

If CI runs after a push or a merge, it will probably run CI with the appropriate revision (by luck).

If CI is scheduled after a more recent commit, or if an older revision gets published with a merge, it will run with a wrong revision.

Example of CI log:

Cloning hg repository...
requesting all changes
adding changesets
adding manifests
adding file changes
added 183 changesets with 391 changes to 92 files (+8 heads)
new changesets a4805fd0d488:a828955eba7f (25 drafts)
updating to branch default
64 files updated, 0 files merged, 0 files removed, 0 files unresolved
just before HgSha
Checking out  as branch/default... (skip)
hg checkout -r