Handle case where returned object from a Watch is not a Pod

[harjsing7]

Description

The Watch function, when passed in interface of v1.PodInterface assumes that the returned type is always of *corev1.Pod, this is not always the case and can result in panics. Here is a simple log of a panic that I hit:

2023-04-17T16:10:31Z | INFO | 2023/04/17 16:10:31 panic: interface conversion: runtime.Object is *v1.Status, not *v1.Pod
2023-04-17T16:10:38Z | INFO | 2023/04/17 16:10:38 
2023-04-17T16:10:38Z | INFO | 2023/04/17 16:10:38 goroutine 101 [running]:
2023-04-17T16:10:38Z | INFO | 2023/04/17 16:10:38 github.com/adobe/rules_gitops/testing/it_sidecar/stern.Watch.func1()
2023-04-17T16:10:38Z | INFO | 2023/04/17 16:10:38 	external/com_adobe_rules_gitops/testing/it_sidecar/stern/watch.go:62 +0x958
2023-04-17T16:10:38Z | INFO | 2023/04/17 16:10:38 created by github.com/adobe/rules_gitops/testing/it_sidecar/stern.Watch
2023-04-17T16:10:38Z | INFO | 2023/04/17 16:10:38 	external/com_adobe_rules_gitops/testing/it_sidecar/stern/watch.go:53 +0x305

Related Issue

Motivation and Context

Fix panic.

How Has This Been 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 change)

Checklist:

• I have signed the Adobe Open Source CLA.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.