Remove documentation website files

[ADubhlaoich]

Proposed changes

This commit removes the documentation website files, which have been migrated to the main documentation repository. It also includes some changes to configuration files that are redundant, such as removing the deployment action from the repository.

Some configuration changes have been left in place for context, and there will likely be some future follow up work to re-integrate certain automations as part of enhancements to the documentation repository.

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

[vepatel]

egrep -v "^site/" can be removed from https://github.com/nginx/kubernetes-ingress/blob/docs/remove-website-files/.github/workflows/ci.yml#L62

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 52.82%. Comparing base (71639ef) to head (6d99e6a).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7915      +/-   ##
==========================================
+ Coverage   52.67%   52.82%   +0.15%     
==========================================
  Files          90       90              
  Lines       21598    21671      +73     
==========================================
+ Hits        11376    11447      +71     
- Misses       9745     9747       +2     
  Partials      477      477              

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[vepatel]

some more changes:

• https://github.com/nginx/kubernetes-ingress/blob/docs/remove-website-files/CONTRIBUTING.md?plain=1#L34
• https://github.com/nginx/kubernetes-ingress/blob/docs/remove-website-files/README.md?plain=1#L145
• https://github.com/nginx/kubernetes-ingress/blob/docs/remove-website-files/.pre-commit-config.yaml#L3
• https://github.com/nginx/kubernetes-ingress/blob/docs/remove-website-files/.pre-commit-config.yaml#L11
• https://github.com/nginx/kubernetes-ingress/blob/docs/remove-website-files/.github/workflows/codeql-analysis.yml#L38
• https://github.com/nginx/kubernetes-ingress/blob/docs/remove-website-files/CODEOWNERS#L2
• https://github.com/nginx/kubernetes-ingress/blob/docs/remove-website-files/.fossa.yml#L7

below scripts needs updating for docs auto-update but might be out of scope for this PR:

• https://github.com/nginx/kubernetes-ingress/blob/docs/remove-website-files/.github/scripts/release-notes-update.sh#L9
• https://github.com/nginx/kubernetes-ingress/blob/docs/remove-website-files/.github/scripts/release-version-update.sh#L12

[ADubhlaoich]

@vepatel Incorporating the feedback now.

I'm not brave enough to touch the release automation files, hahaha.