add transparent init function

[MarlonGamez]

Related: #4915, #5141

Description
Adds the function that will be used for transparent init functionality along with its unit tests.

Follow-up Work (remove if N/A)
Plumb this into skaffold's code that tries to parse in the skaffold config from disk. If nothing is found, this function will be called to try and generate a config for the user.

[codecov]

Codecov Report

Merging #5155 (f04627f) into master (c105818) will decrease coverage by 0.04%.
The diff coverage is 80.00%.

@@            Coverage Diff             @@
##           master    #5155      +/-   ##
==========================================
- Coverage   72.35%   72.30%   -0.05%     
==========================================
  Files         382      384       +2     
  Lines       13589    13621      +32     
==========================================
+ Hits         9832     9849      +17     
- Misses       3038     3050      +12     
- Partials      719      722       +3     

Impacted Files	Coverage Δ
pkg/skaffold/initializer/transparent.go	80.00% <80.00%> (ø)
cmd/skaffold/app/tips/tips.go	54.54% <0.00%> (-12.13%)	⬇️
pkg/skaffold/util/tar.go	50.66% <0.00%> (-5.34%)	⬇️
cmd/skaffold/app/cmd/util.go	65.71% <0.00%> (-0.96%)	⬇️
pkg/skaffold/runner/runner.go	0.00% <0.00%> (ø)
pkg/skaffold/initializer/build/util.go	100.00% <0.00%> (ø)
cmd/skaffold/app/cmd/test.go	53.84% <0.00%> (ø)
cmd/skaffold/app/cmd/cmd.go	66.15% <0.00%> (+0.26%)	⬆️
pkg/skaffold/runner/build_deploy.go	69.89% <0.00%> (+1.00%)	⬆️

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