Make quote function to render pointers in the template properly

[nabokihms]

What this PR does / why we need it:

For now, the reason why location is denied printed in an Nginx configuration file via comment.
But it looks unclear because we see the only pointer, not the error message itself.

For example, the log of nginx contoller configuration change.

-                       # Location denied. Reason: "0xc000323440"
+                       # Location denied. Reason: "0xc000c0f560"
                        return 503;

This happens, because quote function in templates works incorrectly with pointers. And the Denied field in the Location structure is a pointer.

This PR provides a fix for the quote function.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

How Has This Been Tested?

I tested the patched docker image in the ordinary kubeadm installed Kubernetes cluster. I also added the necessary unit test.

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added tests to cover my changes.
• All new and existing tests passed.

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[aledbf]

/check-cla

[aledbf]

@nabokihms please check the commit

[nabokihms]

@aledbf I fixed cla problems.

[aledbf]

/ok-to-test

[codecov-io]

Codecov Report

Merging #5213 into master will increase coverage by 0.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #5213      +/-   ##
==========================================
+ Coverage   58.61%   58.62%   +0.01%     
==========================================
  Files          88       88              
  Lines        6872     6874       +2     
==========================================
+ Hits         4028     4030       +2     
  Misses       2402     2402              
  Partials      442      442

Impacted Files	Coverage Δ
internal/ingress/controller/template/template.go	80.08% <100%> (+0.05%)	⬆️

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[aledbf]

/lgtm
/approve

[aledbf]

@nabokihms thanks!

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: aledbf, nabokihms

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