Set run_as_user to root only on < 2.8.0.  I don't recall the exat bug I
worked around in 2.7 but I do recall needing this.  No longer appears to
be an issue in >= 2.8.0.

ref: PR #26
Merge pull request #31 from hubspotdevops/run_as_user

Set run_as_user to root only on < 2.8.0.

Resolves #26 reported by and with initial fix by @sharkannon