chore: Add Kevin Webb to humans.txt (#51093)

## Problem

Kevin Webb joined team and needs to add name to humans.txt as part of
onboarding

## Solution

Edited humans.txt and added Kevin Webb 

## Review instructions

Confirm name is correctly alphabetized.

## Checklist

Check all before review:

- [x] I have read
[CONTRIBUTING.md](https://github.com/supabase/supabase/blob/master/CONTRIBUTING.md)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Documentation**
* Updated the team listing to include Kevin Webb, keeping the published
team information current. This change is visible in the project’s public
documentation.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

apps/docs/public/humans.txt

@@ -193,6 +193,7 @@ Kevin Brolly
 Kevin Grüneberg
 Kevin Shaffer-Morrison
 Kevin Strong-Holte
+Kevin Webb
 Kody Jackson
 Kostas Botsas
 Krishna Sai Vandavasi