Change pipeline var operations []OpUnion to public

[myles-block]

What this PR does / why we need it:

Current implementation doesn't allow for alteration of the Pipeline field: operations. Here I have changed field to public.

Special notes for your reviewer:

Does this PR introduce a user-facing and/or backwards incompatible change?:

NONE

Does this PR require updating code package or user-facing documentation?:

NONE

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}