Bug 1718823 - Disable GC zeal for weakmap-nursery-value.js test r=arai

Differential Revision: https://phabricator.services.mozilla.com/D119059

js/src/jit-test/tests/gc/weakmap-nursery-value.js

@@ -1,5 +1,9 @@
 // Bug 1715471
 
+// This test relies on triggering GC at precise points. GC zeal modes
+// interfere with this.
+gczeal(0);
+
 // This test requires enqueueMark, which is only available in a debugging
 // build.
 if (!this.enqueueMark) quit(0);