test: assert.equal -> assert.strictEqual

changes assert.equal to assert.strictEqual to ensure specificity

PR-URL: https://github.com/nodejs/node/pull/10067
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>

test/parallel/test-crypto-domain.js

@@ -13,7 +13,7 @@ function test(fn) {
   var ex = new Error('BAM');
   var d = domain.create();
   d.on('error', common.mustCall(function(err) {
-    assert.equal(err, ex);
+    assert.strictEqual(err, ex);
   }));
   var cb = common.mustCall(function() {
     throw ex;