feat(docker creds) can mount docker config into kaniko pod

[garethjevans]

No description provided.

[codecov-io]

Codecov Report

Merging #1466 into master will decrease coverage by 0.41%.
The diff coverage is 1.88%.

@@            Coverage Diff            @@
##           master   #1466      +/-   ##
=========================================
- Coverage   44.42%     44%   -0.42%     
=========================================
  Files         112     112              
  Lines        4642    4688      +46     
=========================================
+ Hits         2062    2063       +1     
- Misses       2373    2418      +45     
  Partials      207     207

Impacted Files	Coverage Δ
pkg/skaffold/build/kaniko/kaniko.go	0% <0%> (ø)	⬆️
pkg/skaffold/build/kaniko/secret.go	0% <0%> (ø)	⬆️
pkg/skaffold/schema/defaults/defaults.go	44.73% <8.33%> (-4.29%)	⬇️

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[priyawadhwa]

Thanks for contributing this fix! Left a couple comments.

[googlebot]

So there's good news and bad news.

👍 The good news is that everyone that needs to sign a CLA (the pull request submitter and all commit authors) have done so. Everything is all good there.

😕 The bad news is that it appears that one or more commits were authored or co-authored by someone other than the pull request submitter. We need to confirm that all authors are ok with their commits being contributed to this project. Please have them confirm that here in the pull request.

Note to project maintainer: This is a terminal state, meaning the cla/google commit status will not change from this state. It's up to you to confirm consent of all the commit author(s), set the cla label to yes (if enabled on your project), and then merge this pull request when appropriate.

[googlebot]

CLAs look good, thanks!

[priyawadhwa]

This looks really good, just a couple more comments.

Could you also please add these additions to the annotated-skaffold.yaml for documentation? Thanks so much!

[priyawadhwa]

LGTM, thanks so much for contributing this feature!