Fix CustomTagger docs

[nkubala]

fixes #4614

#4588 added a new TagPolicy, CustomTagger, which contains one or more TaggerComponents, each of which itself is a TagPolicy.

since the TagPolicy was inlined, our schema generator was removing it from the generated definition properties - this was causing a nil pointer exception in the javascript.

once this issue was fixed, we have another issue. our templater generates HTML for every schema definition, and nests HTML for every nested schema definition - this means that TagPolicy -> CustomTagger -> TaggerComponent -> TagPolicy causes an infinite loop in the schema generation.

the fix here is to add a new yamlTag, skipTrim, which skips trimming off inlined definitions when set. additionally, our templater will now special case TaggerComponent and yield empty HTML rather than recurse into nested definitions, avoiding the infinite loop.

NOTE: this will fail the schema version check, since this technically updates a released schema version. however, since this is just a yaml tag update and NOT a user facing change, I believe this should be safe. once this is merged to master, all subsequent schema version checks will pass (assuming they don't actually change the released schema).

[codecov]

Codecov Report

Merging #4621 into master will decrease coverage by 0.00%.
The diff coverage is 63.63%.

@@            Coverage Diff             @@
##           master    #4621      +/-   ##
==========================================
- Coverage   73.18%   73.17%   -0.01%     
==========================================
  Files         337      337              
  Lines       13261    13272      +11     
==========================================
+ Hits         9705     9712       +7     
- Misses       2947     2950       +3     
- Partials      609      610       +1     

Impacted Files	Coverage Δ
pkg/skaffold/schema/latest/config.go	100.00% <ø> (ø)
pkg/skaffold/yamltags/tags.go	95.55% <63.63%> (-4.45%)	⬇️

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[container-tools-bot]

Please visit http://35.236.24.125:1313 to view changes to the docs.

[tejal29]

http://35.236.24.125:1313/docs/references/yaml/ is up and running.