test: add regression test for v8.getHeapSnapshot() crash

Fixes: nodejs#35559

Author: addaleax

test/parallel/test-v8-getheapsnapshot-twice.js

@@ -0,0 +1,9 @@
+'use strict';
+require('../common');
+const v8 = require('v8');
+
+// Regression test for https://github.com/nodejs/node/issues/35559
+// It is important that the return value of the first call is not used, i.e.
+// that the first snapshot is GC-able while the second one is being created.
+v8.getHeapSnapshot();
+v8.getHeapSnapshot();