De-duplicate and simplify code in the controllers unit tests

[willie-yao]

/kind cleanup

What needs cleanup:
Currently, the unit tests in the controllers package contains lots of duplicated code, mostly in the form of test objects. Many of these objects are re-defined in each test file with very little change in between them.

For example, this test cluster object is re-defined 10 times in the controllers package.

Describe the solution you'd like
We should create a file that stores all of the common helper functions and objects that are used for unit tests in the controllers package.

Files to change:

• All unit test files in the controllers package

Anything else you would like to add:
[Miscellaneous information that will assist in solving the issue.]

[willie-yao]

This is also a follow-up from a discussion in #4208
#4208 (comment)

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/lifecycle stale

[nawazkh]

/remove-lifecycle stale

[k8s-triage-robot]

The Kubernetes project currently lacks enough contributors to adequately respond to all issues.

This bot triages un-triaged issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Mark this issue as fresh with /remove-lifecycle stale
• Close this issue with /close
• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/lifecycle stale

[willie-yao]

/remove-lifecycle stale