fix: create namespace when running TestSuite

[chenmj11]

What this PR does / why we need it:

The tests in a TestSuite fail, because the specified namespace does not exist.

kuttl-test.yaml

apiVersion: kuttl.dev/v1beta1
kind: TestSuite
namespace: test
timeout: 60
reportName: test
reportFormat: JSON 

error logs

    logger.go:42: 13:48:07 | pod | Ignoring pod-assert.yaml as it does not match file name regexp: ^(\d+)-(?:[^\.]+)(?:\.yaml)?$  
    logger.go:42: 13:48:07 | pod | Ignoring pod.yaml as it does not match file name regexp: ^(\d+)-(?:[^\.]+)(?:\.yaml)?$  
    logger.go:42: 13:48:07 | pod | Skipping creation of user-supplied namespace: test  
    logger.go:42: 13:48:07 | pod/0-step | starting test step 0-step  
    case.go:366: failed in step 0-step  
    case.go:368: namespaces "test" not found  

*Automatically closes linked issue when PR is merged. Fixes 512