Revert "fix(custom-resources): Custom resource provider framework not…

… passing `ResponseURL` to user function" (#21109)

This PR did not actually fix the issue with custom resources, it just passed a `ResponseURL: '...'`, which isn't a usable URL. Leaving it as a sanitized string makes it appear as if the `ResponseURL` is available, but it actually isn't. Reverting this PR to not give the false impression that `ResponseURL` is usable.

Reverts #21065

packages/@aws-cdk/custom-resources/lib/provider-framework/runtime/framework.ts

@@ -105,7 +105,9 @@ async function invokeUserFunction<A extends { ResponseURL: '...' }>(functionArnE
   // automatically by the JavaScript SDK.
   const resp = await invokeFunction({
     FunctionName: functionArn,
-    Payload: JSON.stringify(sanitizedPayload),
+
+    // Strip 'ResponseURL' -- the downstream CR doesn't need it and can only log it by accident
+    Payload: JSON.stringify({ ...sanitizedPayload, ResponseURL: undefined }),
   });
 
   log('user function response:', resp, typeof(resp));