When running the release of Flutter 3.7.4, we did not include a dart revision as there was no Dart release.

Without a dart revision, conductor assumes that there were no engine changes, and does not create an engine PR which is expected. However, our current process adds cherry-picks to release branches manually.

With the new process, we still need to access the head revision of the engine in the release branch to be able to update bin/internal/engine.version in the Framework.

Workaround: Manually create a framework PR that updates the engine revision.

CC: @CaseyHillers @XilaiZhang