Add Gateway API objects to the icons set.

[jDmacD]

Hi People,

The K8s icon set is something I use daily for documentation, presentations, graphing etc.

A Gateway and HTTP Route icon are sorely missed and would make a great addition to the set.

some inspiration

My attempt:

[k8s-ci-robot]

There are no sig labels on this issue. Please add an appropriate label by using one of the following commands:

• /sig <group-name>
• /wg <group-name>
• /committee <group-name>

Please see the group list for a listing of the SIGs, working groups, and committees available.

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.