ci: run msi package job for scheduled pipelines

.. and not the normal 'cerbero deps msvc x86_64' one.

We have to work around a gitlab bug here where the whole
pipeline blocks on manual jobs that are made manual via rules.
The 'allow_failure: true' bit is the recommended workaround
for that until it gets fixed properly.

https://gitlab.com/gitlab-org/gitlab/-/issues/39534#note_458110925
https://gitlab.com/gitlab-org/gitlab/-/merge_requests/24605

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