feat(konnect): require gw discovery, rename gw discovery and release 2.17.0-rc.1

[czeslavo]

What this PR does / why we need it:

Requires Gateway discovery to be enabled when Konnect sync is enabled. As a result, splits the example values for Konnect into the already existing minimal-kong-gd-gateway.yaml and a new minimal-kong-gd-controller-konnect.yaml. Also renames the serviceDiscovery to gatewayDiscovery.

Which issue this PR fixes

Part of Kong/kubernetes-ingress-controller#3581 and #740.

Special notes for your reviewer:

Checklist

[Place an '[x]' (no spaces) in all applicable fields. Please remove unrelated fields.]

• PR is based off the current tip of the main branch.
• Changes are documented under the "Unreleased" header in CHANGELOG.md
• New or modified sections of values.yaml are documented in the README.md
• Commits follow the Kong commit message guidelines

[mflendrich]

Let's go.

In search of renaming leftovers I have: eyeballed the diff, grepped the codebase for sd, service.discovery and servicediscovery - all in a case-insensitive way. Looks good.