Add unit tests for WaitForPodSucceeded

[priyawadhwa]

also renamed WaitForPodCompleted to WaitForPodSucceeded

[codecov-io]

Codecov Report

Merging #2239 into master will decrease coverage by 0.75%.
The diff coverage is 80%.

@@            Coverage Diff             @@
##           master    #2239      +/-   ##
==========================================
- Coverage   60.03%   59.27%   -0.76%     
==========================================
  Files         185      191       +6     
  Lines        7794     7981     +187     
==========================================
+ Hits         4679     4731      +52     
- Misses       2728     2861     +133     
- Partials      387      389       +2

Impacted Files	Coverage Δ
pkg/skaffold/build/cluster/kaniko.go	36.11% <0%> (ø)	⬆️
pkg/skaffold/kubernetes/wait.go	46.05% <100%> (+46.05%)	⬆️
pkg/webhook/labels/labels.go	100% <0%> (ø)
pkg/webhook/kubernetes/deployment.go	0% <0%> (ø)
pkg/webhook/kubernetes/service.go	0% <0%> (ø)
pkg/webhook/github/github.go	0% <0%> (ø)
pkg/webhook/gcs/gcs.go	0% <0%> (ø)
pkg/webhook/kubernetes/cleanup.go	0% <0%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update bca710f...f1bdcb0. Read the comment docs.

[balopat]

LGTM!