Heptapod CI: re-require the omnibus-pkg tag for main build

We have newly created group runners on the OSUOSL machines, bearing
the tag that obviously could not be set on the instance runners.
Additional benefit: they use the S3 cache.

Backed out changeset 59643c3703d7

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branch : heptapod
14 jobs for !59 with topic/heptapod/license-pbm in 59 minutes and 56 seconds
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