Wrap tester in SkaffoldRunner to improve SkaffoldLogEvent labelling

[MarlonGamez]

Fixes: #5368

Description
This PR adds proper labelling of SkaffoldLogEvents that come from Skaffold's testing phase. I've also added a Test function onto the SkaffoldRunner rather than embedding a tester. This allows us to use output.WithEventContext in a way that's more consistent with how we use it for build and deploy phases.

SkaffoldLogEvents starting from Starting Test... up to, but not including, Tags used in deployment should now have proper task information set.

Tests were not added for SkaffoldRunner.Test as there is no real logic there, it's simply calling the underlying data structures Test function.

[codecov]

Codecov Report

Merging #6469 (afbaf6d) into main (8303f00) will decrease coverage by 0.01%.
The diff coverage is 90.00%.

@@            Coverage Diff             @@
##             main    #6469      +/-   ##
==========================================
- Coverage   70.28%   70.26%   -0.02%     
==========================================
  Files         510      511       +1     
  Lines       22988    22993       +5     
==========================================
- Hits        16157    16156       -1     
- Misses       5775     5779       +4     
- Partials     1056     1058       +2     

Impacted Files	Coverage Δ
pkg/skaffold/runner/v1/dev.go	73.12% <0.00%> (ø)
pkg/skaffold/runner/v1/runner.go	0.00% <ø> (ø)
pkg/skaffold/test/test_factory.go	76.19% <ø> (-1.09%)	⬇️
pkg/skaffold/runner/v1/new.go	63.24% <100.00%> (ø)
pkg/skaffold/runner/v1/test.go	100.00% <100.00%> (ø)
pkg/skaffold/log/stream/stream.go	71.42% <0.00%> (-14.29%)	⬇️
pkg/skaffold/docker/image.go	65.56% <0.00%> (-1.00%)	⬇️

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[tejal29]

The code changes look good. Can you please add the new event changes?

[tejal29]

Please specify the event difference.

[MarlonGamez]

@tejal29 SkaffoldLogEvents starting from Starting Test... up to, but not including, Tags used in deployment should now have proper task information set. I updated the PR description to include this information 👍🏼