Add namespace when calling pods_by_resource

[martin-mat]

Description

The namespace is needed to be passed as a parameter when calling pods_by_resource of kubectl client. Impacted tests: single_process_type, prometheus_traffic Also adding non-default namespace to respective spec tests.

Issues:

Refs: #2030

How has this been tested:

• [ ] Covered by existing integration testing
• [ ] Added integration testing to cover
• [ ] Verified all A/C passes
  • [ ] develop
  • [ ] master
  • [ ] tag/other branch
• [ ] Test environment
  • [ ] Shared Packet K8s cluster
  • [ ] New Packet K8s cluster
  • [ ] Kind cluster
• [ ] Have not tested

Types of changes:

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Documentation update

Checklist:

Documentation

• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [ ] No updates required.

Code Review

• [ ] Does the test handle fatal exceptions, ie. rescue block

Issue

• [ ] Tasks in issue are checked off