test: show full object diff (#28069)

Co-authored-by: Cheng Zhao <zcbenz@gmail.com>

spec/static/index.html

@@ -91,6 +91,10 @@
   chai.use(require('chai-as-promised'))
   chai.use(require('dirty-chai'))
 
+  // Show full object diff
+  // https://github.com/chaijs/chai/issues/469
+  chai.config.truncateThreshold = 0;
+
   const runner = mocha.run(() => {
     // Ensure the callback is called after runner is defined
     setTimeout(() => {