test: check pod ready status before getting name

[aramase]

What this PR does / why we need it:

• Checks if the provider pods are ready before getting the pod name

Which issue(s) this PR fixes (optional, using fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when the PR gets merged):
Fixes #

Special notes for your reviewer:
Prevents flakes similar to -

not ok 1 install azure provider
# (in test file test/bats/azure.bats, line 44)
#   `AZURE_PROVIDER_POD=$(kubectl get pod --namespace $NAMESPACE -l app=csi-secrets-store-provider-azure -o jsonpath="{.items[0].metadata.name}")' failed
# error: error executing jsonpath "{.items[0].metadata.name}": Error executing template: array index out of bounds: index 0, length 0. Printing more information for debugging the template:
# 	template was:
# 		{.items[0].metadata.name}
# 	object given to jsonpath engine was:
# 		map[string]interface {}{"apiVersion":"v1", "items":[]interface {}{}, "kind":"List", "metadata":map[string]interface {}{"resourceVersion":"", "selfLink":""}}
# 
# 

where the provider pod is not yet scheduled

/kind flake

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: aramase

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• OWNERS [aramase]

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[ritazh]

/lgtm