Change void_return_test to not use eval

eval is disallowed by CSP and the dart2js-minified-csp-linux-chrome
bot is currently red. This uses Math.max, which should be available
both on d8 and with CSP enabled.

Change-Id: I5e348a72d50cf10db713934151473f0d15782ba3
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/421502
Commit-Queue: Ömer Ağacan <[email protected]>
Auto-Submit: Srujan Gaddam <[email protected]>
Reviewed-by: Ömer Ağacan <[email protected]>

Author: srujzs

tests/lib/js/static_interop_test/void_return_test.dart

@@ -6,11 +6,11 @@
 
 import 'dart:js_interop';
 
-@JS()
-external void eval(String code);
+@JS('Math.max')
+external void max(int a, int b);
 
 void main() {
-  Object? x = eval('1 + 1') as dynamic;
+  Object? x = max(1, 2) as dynamic;
 
   // It doesn't matter what this prints, it just shouldn't crash.
   print(x);