fix: clean generated and unit test helper files

[mboersma]

Reason for Change:

make clean by tradition should clean up all generated and temporary files. This adds some droppings that were missed.

Issue Fixed:

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Notes:

[jackfrancis]

/lgtm

[acs-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jackfrancis, mboersma

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [jackfrancis,mboersma]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[mboersma]

/hold until #1088 is merged, since that will have us check in the generated go files intentionally.

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@5f86d3d). Click here to learn what that means.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master    #1151   +/-   ##
=========================================
  Coverage          ?   74.43%           
=========================================
  Files             ?      131           
  Lines             ?    18317           
  Branches          ?        0           
=========================================
  Hits              ?    13634           
  Misses            ?     3902           
  Partials          ?      781

[mboersma]

/hold cancel