[feat gw-api]update reference grant check and route status

[shuqz]

Description

• Modified route status behavior
  • Before: when resolvedRef is false, we mark accepted as false too. Now (aligns with conformance test requirement): only resolvedRef reason can impact resolvedRef status. same for Accepted.
  • this change got us passed following test cases:
  • HTTPRouteInvalidBackendRefUnknownKind
  • HTTPRouteInvalidCrossNamespaceBackendRef
  • HTTPRouteInvalidNonExistentBackendRef
  • HTTPRoutePartiallyInvalidViaInvalidReferenceGrant
• Modified reference grant check logic
  • we are returning 503 instead 500 when no backend service, conformance test is expecting 500
  • we did not do From.Group and To.Group check, added it
  • this change got us passed following test cases:
  • HTTPRouteInvalidReferenceGrant
  • HTTPRouteReferenceGrant
• Modified e2e test
  • based on above logic modification, changed corresponding e2e test
  • explicitly set targetType as instance in alb/nlb instance test cases. we were not explicitly set instance type and reply on using default value. but when i was doing test, since i have --default-target-type=ip in deployment, it is overriding the default value. i want to eliminating similar issue to e2e tests by explicitly setting it to instance (just like we set it to ip in ip tests)
  • minor: added tls section in listeners, we do not process it but it needs to be provided to pass validation and continue test (found it during e2e testing)

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the docs directory)
• Manually tested

ginkgo -v -r test/e2e/gateway --  -ginkgo.focus="with ALB ip target configuration with basic HTTPRoute"
Ran 1 of 28 Specs in 552.775 seconds
SUCCESS! -- 1 Passed | 0 Failed | 0 Pending | 27 Skipped
PASS

ginkgo -v -r test/e2e/gateway --  -ginkgo.focus="with ALB instance target configuration with basic HTTPRoute"
Ran 1 of 28 Specs in 554.888 seconds
SUCCESS! -- 1 Passed | 0 Failed | 0 Pending | 27 Skipped
PASS

ginkgo -v -r test/e2e/gateway --  -ginkgo.focus="with NLB ip target configuration, using readiness gates false"
Ran 1 of 28 Specs in 963.706 seconds
SUCCESS! -- 1 Passed | 0 Failed | 0 Pending | 27 Skipped
PASS

• Made sure the title of the PR is a good description that can go into the release notes

BONUS POINTS checklist: complete for good vibes and maybe prizes?! 🤯

• Backfilled missing tests for code in same general area 🎉
• Refactored something and made the world a better place 🌟

[shraddhabang]

No message?

[shuqz]

i felt the status and reason combined is pretty intuitive (accepted=true and resolvedref=true). adding a message is basically just repeating the same thing

[zac-nixon]

agreed with Shelley, seems intuitive you don't need additional info for an accepted status.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: shuqz

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

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [shuqz]

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

[shraddhabang]

/lgtm