Support for replacing image names in env vars

[ajbouh]

Specifically env vars that end with _IMAGE

[codecov-io]

Codecov Report

Merging #995 into master will increase coverage by 0.17%.
The diff coverage is 65.45%.

@@            Coverage Diff             @@
##           master     #995      +/-   ##
==========================================
+ Coverage   40.61%   40.79%   +0.17%     
==========================================
  Files          68       68              
  Lines        2969     3010      +41     
==========================================
+ Hits         1206     1228      +22     
- Misses       1639     1657      +18     
- Partials      124      125       +1

Impacted Files	Coverage Δ
pkg/skaffold/deploy/kubectl/images.go	75% <65.45%> (-25%)	⬇️

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[mattfysh]

This will be very handy for kicking off jobs needing the skaffold-tagged image names. For now, a workaround is to annotate the pod that needs the image name, using key "image". It will match and get picked up by the replacer

[tejal29]

Can we please add some tests for it?

[ajbouh]

I don't know how bad the rebase will be so I'm reluctant to invest further in this PR. Also unclear what the appetite for merging this is. Thoughts on these points?

[tejal29]

I think we are thinking of Adding Env Based tagger as part of #922 for skaffold build images.
See #922 (comment) for more details.

I agree, lets close this PR for now and revisit if this is needed once #922 is resolved.

[ajbouh]

What is env based tagger? That sounds like a way to use environment variables to decide on the docker image tag?

If so, that's unrelated to what this PR does

[tejal29]

Yes it unrelated to the PR. Since you mentioned you don't want to invest further at this time, I suggesting revisiting this once build changes are in.
Feel free to re-open this if you want to get this in before that.