support HTTP headers in service API calls

[JimBugwadia]

Explanation

Support HTTP headers in Service API calls

Related issue

Fixes #6833

Milestone of this PR

1.13

Documentation (required for features)

My PR contains new or altered behavior to Kyverno.

• I have sent the draft PR to add or update the documentation and the link is:

What type of PR is this

/kind feature

Proposed Changes

Support HTTP headers in Service API calls:

      context:
        - name: result
          apiCall:
            method: POST
            data:
              - key: foo
                value: bar
              - key: namespace
                value: "{{ `{{ request.namespace }}` }}"
            service:
              url: http://my-service.svc.cluster.local/validation
              headers:
                - key: "UserAgent"
                  value: "Kyverno Policy XYZ"
                - key: "Authorization"
                  value: "Bearer {{ MY_SECRET }}"

Proof Manifests

See unit tests.

Checklist

• I have read the contributing guidelines.
• I have read the PR documentation guide and followed the process including adding proof manifests to this PR.
• This is a bug fix and I have added unit tests that prove my fix is effective.
• This is a feature and I have added CLI tests that are applicable.
• My PR needs to be cherry picked to a specific release branch which is .
• My PR contains new or altered behavior to Kyverno and
  • CLI support should be added and my PR doesn't contain that functionality.

Further Comments

[JimBugwadia]

Added changes from: #11042

[codecov]

Codecov Report

Attention: Patch coverage is 26.92308% with 38 lines in your changes missing coverage. Please review.

Project coverage is 12.21%. Comparing base (be0ad07) to head (5a378d8).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
api/kyverno/v1/zz_generated.deepcopy.go	0.00%	14 Missing ⚠️
...lient/applyconfigurations/kyverno/v1/httpheader.go	0.00%	8 Missing ⚠️
pkg/engine/apicall/executor.go	63.63%	4 Missing and 4 partials ⚠️
...ient/applyconfigurations/kyverno/v1/servicecall.go	0.00%	6 Missing ⚠️
pkg/client/applyconfigurations/utils.go	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #11041      +/-   ##
==========================================
- Coverage   12.22%   12.21%   -0.01%     
==========================================
  Files         945      946       +1     
  Lines       87258    87295      +37     
==========================================
+ Hits        10663    10667       +4     
- Misses      75282    75313      +31     
- Partials     1313     1315       +2     

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[eddycharly]

/cherry-pick release-1.13

[realshuting]

This needs to be documented.