test: Remove string literals for strictEquals/notStrictEquals

test/fixtures/not-main-module.js

@@ -20,6 +20,5 @@
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 const assert = require('assert');
-assert.notStrictEqual(module, require.main, 'require.main should not == module');
-assert.notStrictEqual(module, process.mainModule,
-                      'process.mainModule should not === module');
+assert.notStrictEqual(module, require.main);
+assert.notStrictEqual(module, process.mainModule);

test/parallel/test-async-wrap-trigger-id.js

@@ -13,16 +13,12 @@ process.nextTick(() => {
     triggerAsyncId1 = triggerAsyncId();
     assert.notStrictEqual(
       triggerAsyncId0,
-      triggerAsyncId1,
-      'Async resources having different causal ancestry ' +
-      'should have different triggerAsyncIds');
+      triggerAsyncId1);
   });
   process.nextTick(() => {
     const triggerAsyncId2 = triggerAsyncId();
     assert.strictEqual(
       triggerAsyncId1,
-      triggerAsyncId2,
-      'Async resources having the same causal ancestry ' +
-      'should have the same triggerAsyncId');
+      triggerAsyncId2);
   });
 });