Add release notes for 1.33.3 (#6401)

Co-authored-by: minux <[email protected]>

Author: ikhoon

site/src/pages/release-notes/1.33.3.mdx

@@ -0,0 +1,17 @@
+---
+date: 2025-09-17
+---
+
+## 🛠️ Bug fixes
+
+- Fixed Athenz access token validation to work with RFC-compliant JWKS. #6393
+- <type://FileService> now correctly handles `HEAD` method. #6392 #6395
+
+## 🙇 Thank you
+
+<ThankYou usernames={[
+  'ikhoon',
+  'jrhee17',
+  'minwoox',
+  'trustin'
+]} />