Fixed never ending "Building admin client" messages using grunt dev

no issue
- ember-cli stopped outputting the "Build successful" text that we were looking for as an indication of completion

Gruntfile.js

@@ -195,17 +195,11 @@ const configureGrunt = function (grunt) {
                         grunt.log.write(chunk);
                     }
 
-                    if (chunk.indexOf('Build successful') !== -1) {
+                    if (chunk.indexOf('Slowest Nodes') !== -1) {
                         hasBuiltClient = true;
                     }
                 },
                 stderr: function (chunk) {
-                    // ember-data 3.6.0-3.7.0 outputs a "Circular dependency" warning which we want to ignore
-                    // TODO: remove after upgrading to ember-data 3.8.0 which already filters the output
-                    if (chunk.indexOf('Circular dependency') > -1) {
-                        return;
-                    }
-
                     hasBuiltClient = true;
                     grunt.log.error(chunk);
                 }