docs: Add missing template field

[AndreasBergmeier6176]

Description
Templates work for manifests, too.
So document setValueTemplates since we are actually using it.

User facing changes
Documentation is less incomplete.

Follow-up Work
From the looks of it, there might be more fields missing.

[codecov]

Codecov Report

Attention: 295 lines in your changes are missing coverage. Please review.

Comparison is base (290280e) 70.48% compared to head (f999ef1) 63.72%.
Report is 1068 commits behind head on main.

Files	Patch %	Lines
cmd/skaffold/app/cmd/exec.go	16.32%	40 Missing and 1 partial ⚠️
cmd/skaffold/app/cmd/filter.go	47.27%	22 Missing and 7 partials ⚠️
cmd/skaffold/app/cmd/lsp.go	28.12%	23 Missing ⚠️
cmd/skaffold/app/cmd/verify.go	23.33%	23 Missing ⚠️
cmd/skaffold/app/cmd/fix.go	51.16%	17 Missing and 4 partials ⚠️
cmd/skaffold/app/cmd/inspect_job_manifest_paths.go	60.00%	15 Missing and 1 partial ⚠️
cmd/skaffold/app/cmd/inspect_namespaces.go	50.00%	13 Missing and 1 partial ⚠️
...md/skaffold/app/cmd/inspect_config_dependencies.go	45.83%	12 Missing and 1 partial ⚠️
cmd/skaffold/app/cmd/lint.go	42.85%	12 Missing ⚠️
cmd/skaffold/app/cmd/inspect_build_env.go	60.71%	11 Missing ⚠️
... and 21 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9186      +/-   ##
==========================================
- Coverage   70.48%   63.72%   -6.76%     
==========================================
  Files         515      630     +115     
  Lines       23150    32447    +9297     
==========================================
+ Hits        16317    20678    +4361     
- Misses       5776    10179    +4403     
- Partials     1057     1590     +533     

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