Increase Browserstack Retry limit to avoid potential flakes (there haven't been one yet)

Author: devversion

test/karma.conf.js

@@ -71,9 +71,8 @@ module.exports = (config) => {
     browserStack: {
       project: 'Angular Material Unit Tests',
       startTunnel: false,
-      retryLimit: 1,
+      retryLimit: 3,
       timeout: 1800,
-      pollingTimeout: 20000,
       video: false,
     },
 
@@ -84,6 +83,7 @@ module.exports = (config) => {
 
     browsers: ['ChromeHeadlessLocal'],
     singleRun: false,
+    transports: ['websocket'],
 
     browserConsoleLogOptions: {
       terminal: true,