chore(kong) bump proxy image version

[rainest]

What this PR does / why we need it:

Bumps the Kong version to 3.5.

Checklist

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

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

[pmalek]

If possible next time let's include the actual version we bump to in the commit and PR title 🙏

It will allow easier search and PR/commit discoverability.