chore(conformance): bump gateway-api to v1.5.0

[danehans]

What type of PR is this?
/kind cleanup
/area conformance-machinery

What this PR does / why we need it:
Bump the ./conformance module's Gateway API dependencies to v1.5.0.

This updates both:

• sigs.k8s.io/gateway-api
• sigs.k8s.io/gateway-api/conformance

and refreshes conformance/go.sum accordingly.

Which issue(s) this PR fixes:
N/A

Does this PR introduce a user-facing change?:

NONE

[k8s-ci-robot]

@danehans: The label(s) area/conformance-machinery cannot be applied, because the repository doesn't have them.

Details

In response to this:

What type of PR is this?
/kind cleanup
/area conformance-machinery

What this PR does / why we need it:
Bump the ./conformance module's Gateway API dependencies to v1.5.0.

This updates both:

• sigs.k8s.io/gateway-api
• sigs.k8s.io/gateway-api/conformance

and refreshes conformance/go.sum accordingly.

Validation:

• cd conformance && go test $(go list ./... | grep -v '^sigs.k8s.io/gateway-api-inference-extension/conformance$')
• cd conformance && go test ./... currently fails in TestConformance because the module's only _test.go entrypoint is the full conformance harness, and the active kube context does not have GatewayClass/gateway-conformance installed.

Which issue(s) this PR fixes:
Fixes #

Does this PR introduce a user-facing change?:

NONE

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[netlify]

✅ Deploy Preview for gateway-api-inference-extension ready!

Name	Link
🔨 Latest commit	4791c88
🔍 Latest deploy log	https://app.netlify.com/projects/gateway-api-inference-extension/deploys/69ada0eeb903290008f02abf
😎 Deploy Preview	https://deploy-preview-2519--gateway-api-inference-extension.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 project configuration.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: danehans

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Details

Needs approval from an approver in each of these files:

• OWNERS [danehans]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[kfswain]

/lgtm