Add test utilities for installing NGF

[sjberman]

Problem:

1. In order to start running system tests, we need a framework in place.
2. Sometimes when installed, NGF would start before the control plane CRD existed.

Solution:

1. Implement a basic framework that installs and uninstalls NGF.
2. Add a polling loop to find the control plane CRD before exiting.

Testing: Verified no errors in setup and teardown

Closes #985

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

[kate-osborn]

LGTM!