Add SNI to NIC JWT Policy

[javorszky]

Proposed changes

Closes #7427

Adds the ability to specify SNI related options for jwt policies.

There are two configuration options:

• sniEnabled, which controls the value of the proxy_ssl_server_name nginx directive, and
• sniName, which controls the value of the proxy_ssl_name` nginx directive

Specifying sniName without SNI being enabled will result in an error.

Documentation PR: nginx/documentation#795

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

[codecov]

Codecov Report

Attention: Patch coverage is 68.00000% with 8 lines in your changes missing coverage. Please review.

Project coverage is 52.96%. Comparing base (45add90) to head (7c2c3e4).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/apis/configuration/validation/policy.go	57.89%	7 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7993      +/-   ##
==========================================
+ Coverage   52.95%   52.96%   +0.01%     
==========================================
  Files          90       90              
  Lines       21729    21749      +20     
==========================================
+ Hits        11506    11519      +13     
- Misses       9746     9752       +6     
- Partials      477      478       +1     

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[vepatel]

@haywoodsh can we add same description here in the keys as the PR in docs

[vepatel]

nginx/documentation#795

[haywoodsh]

Okay working on it. I guess the review for the docs will be done in this PR then.

[vepatel]

@haywoodsh same test at the route level line#2371