Update GatewayAPI to v1.4.0

[ciarams87]

Proposed changes

Problem: We don't currently support the latest version of the Gateway API

Solution: Upgrade to v1.4.0, including BackendTLSPolicy promotion -> v1 and other Policy type promotion -> v1. See the full changelog. Also enables the conformance tests for BackendTLSPolicy.

This also requires upgrading the inference extension from 1.0.2 -> 1.1.0 to resolve dependency conflicts.

Testing: unit testing, running the pipeline for conformance and functional testing, but the RC run passed conformance.

Please focus on (optional): If you any specific areas where you would like reviewers to focus their attention or provide
specific feedback, add them here.

Closes #4034
Closes #3795

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

Release notes

If this PR introduces a change that affects users and needs to be mentioned in the release notes,
please add a brief note that summarizes the change.

Upgraded Gateway API to v1.4.0. Upgraded Inference Extension to v1.1.0. 

[codecov]

Codecov Report

❌ Patch coverage is 69.64286% with 17 lines in your changes missing coverage. Please review.
✅ Project coverage is 86.02%. Comparing base (dc0007d) to head (ed6e380).

Files with missing lines	Patch %	Lines
internal/controller/state/conditions/conditions.go	0.00%	15 Missing ⚠️
internal/controller/state/graph/gatewayclass.go	60.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@ Coverage Diff @@ ## main #4166 +/- ## ========================================== + Coverage 86.00% 86.02% +0.01%  ========================================== Files 131 131 Lines 14111 14106 -5 Branches 35 35 ========================================== - Hits 12136 12134 -2  + Misses 1772 1767 -5  - Partials 203 205 +2 

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[bjee19]

Looks like this PR is also updating inference extension from 1.0.2 -> 1.1.0, which i guess is fine, but was that intentional? If so we should add that to the PR notes.

[ciarams87]

Looks like this PR is also updating inference extension from 1.0.2 -> 1.1.0, which i guess is fine, but was that intentional? If so we should add that to the PR notes.

@bjee19 Good catch Ben - yes I needed to update this as well as there was a misnamed variable being referenced somewhere causing conformance tests to fail. I named the commit (Upgrade inference extension to v1.1.0 to fix conformance tests) but neglected to update the notes. Thank you!!

[salonichf5]

lgtm

[salonichf5]

We should update the release note with info about Inference extension version bump