[plugin][openshift-tests] What is the impact when running suites in serial mode?

We need to evaluate whether there is any benefit to the results and validation environment when running the suites in serial mode.

why? We are seeing a slightly high number of failures in 'know platforms' such as AWS, even checking the existing flakes. We need to check if the parallel is impacting the results.

Goal:

• Run OPCT on AWS (Platform=None) with default execution (parallel)
• Run OPCT on AWS (Platform=None) with both suites (kubernetes/conformance and openshift/conformance) in serial mode

Collect the results of both and measure the differences, focusing on:

• failure ratio
• plugin execution time and total execution time