Change doctests ci launch time
# What does this PR do?

Current doctests CI is launched at 0h (GTM+0), but the docker images are built at  1h (GTM+0), while modeling CI is at  2h (GTM+0).

It happens a few times that we change something in doctest docker image workflow file, expect the failed tests will pass in the next run, and turns out it is not - as the next run is launched 1 hour before the new image is built.

To avoid confusion, this PR **change the doctest launch time to be the same as the modeling CI time - which is after the docker image build CI**.
_The documentation is not available anymore as the PR was closed or merged._