feat(handlers): authz authrequest authelia url

[james-d-elliott]

This adjusts the AuthRequest Authz implementation behave similarly to the other implementations in as much as Authelia can return the relevant redirection to the proxy and the proxy just utilizes it if possible. In addition it swaps the HAProxy examples over to the ForwardAuth implementation as that's now supported.

[authelia]

Artifacts

These changes are published for testing on Buildkite, DockerHub and GitHub Container Registry.

Docker Container

• docker pull authelia/authelia:feat-nginx-proxy-url
• docker pull ghcr.io/authelia/authelia:feat-nginx-proxy-url

[codecov]

Codecov Report

Merging #5181 (97e23c8) into master (fa250ea) will increase coverage by 0.08%.
The diff coverage is 61.78%.

❗ Current head 97e23c8 differs from pull request most recent head b503f6c. Consider uploading reports for the commit b503f6c to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5181      +/-   ##
==========================================
+ Coverage   68.01%   68.10%   +0.08%     
==========================================
  Files         283      283              
  Lines       21230    21269      +39     
  Branches      443      443              
==========================================
+ Hits        14440    14485      +45     
+ Misses       6016     6013       -3     
+ Partials      774      771       -3     

Flag	Coverage Δ
backend	68.49% <61.78%> (+0.09%)	⬆️
frontend	63.20% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
internal/handlers/handler_authz_types.go	83.33% <ø> (ø)
internal/handlers/handler_oidc_userinfo.go	0.00% <0.00%> (ø)
internal/handlers/handler_authz_util.go	31.08% <2.56%> (-7.91%)	⬇️
internal/handlers/handler_authz_authn.go	79.93% <72.00%> (+0.19%)	⬆️
internal/middlewares/authelia_context.go	69.61% <84.61%> (+0.29%)	⬆️
internal/handlers/handler_authz.go	96.21% <88.46%> (+1.05%)	⬆️
internal/handlers/handler_authz_builder.go	89.10% <100.00%> (+11.24%)	⬆️
...nternal/handlers/handler_authz_impl_authrequest.go	100.00% <100.00%> (ø)
internal/handlers/handler_authz_impl_extauthz.go	92.30% <100.00%> (+1.13%)	⬆️
...nternal/handlers/handler_authz_impl_forwardauth.go	100.00% <100.00%> (ø)
... and 3 more

... and 3 files with indirect coverage changes

[netlify]

✅ Deploy Preview for authelia-staging ready!

Name	Link
🔨 Latest commit	8d117be
🔍 Latest deploy log	https://app.netlify.com/sites/authelia-staging/deploys/6430edad9812c500082172fe
😎 Deploy Preview	https://deploy-preview-5181--authelia-staging.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site settings.

[nightah]

Just a couple small nits and considerations, WDYT?

[autheliabot]

🚫 [golangci] _{reported by reviewdog 🐶}
File is not goimports-ed with -local github.com/authelia/authelia (goimports)