fix: use minified JSON in logging-example fixture

Changed JSON.stringify to not pretty-print so the response matches
what the integration test expects (minified JSON without spaces).

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Signed-off-by: Lars Trieloff <lars@trieloff.net>

Author: claude

test/fixtures/logging-example/index.js

@@ -84,7 +84,7 @@ export function main(req, context) {
       timestamp: new Date().toISOString(),
     };
 
-    return new Response(JSON.stringify(response, null, 2), {
+    return new Response(JSON.stringify(response), {
       headers: {
         'Content-Type': 'application/json',
       },