ConfigTracker: Scan envFrom in init-containers

[kazukousen]

Currently, the ConfigTracker is not supported scanning initContainer's environments.
this PR supports that. it is useful when we want to switch the path to the data at the timing of starting initContainer.

How can I add tests to scan envFrom in initContainer?
I guess I would add the initContainer spec to the struct returned by the newDeploymentControllerTest method in deployment_fixture_test.go.

[codecov-commenter]

Codecov Report

Merging #914 (b26b49f) into main (39a3898) will increase coverage by 0.04%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #914      +/-   ##
==========================================
+ Coverage   56.78%   56.83%   +0.04%     
==========================================
  Files          69       69              
  Lines        5727     5729       +2     
==========================================
+ Hits         3252     3256       +4     
+ Misses       1990     1988       -2     
  Partials      485      485              

Impacted Files	Coverage Δ
pkg/canary/config_tracker.go	84.30% <100.00%> (+1.04%)	⬆️

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[stefanprodan]

I guess I would add the initContainer spec to the struct returned by the newDeploymentControllerTest method in deployment_fixture_test.go.

Yes please do that.

[kazukousen]

please check out b26b49f
test fixtures has a lot of duplicate code, but I intentionally left intact to minimize the impact on the existing code base.
(on the other hand, there is room for refactoring, such as sharing code between Deployment/DaemonSet.)

[stefanprodan]

on the other hand, there is room for refactoring, such as sharing code between Deployment/DaemonSet

Yes indeed, if you have the time maybe you could open a different PR for the tests refactoring.

[stefanprodan]

LGTM

Thanks @kazukousen 🏅