New e2e test suite (#555)

* add @cypress/schematic as a dev dependency

* replace protractor with cypress

* remove the boilerplate test

* add the cypress-wait-until helper library

* add cypress-wait-until to all tests

* add signet to stg proxy config

* add proxy config for production

* add environment configs to angular.json

* update e2e target to use the production proxy

* update serve and start scripts to use the new environment config

* add the concurrently lib to the dev dependencies

* fix missing import

* ignore videos and screenshots saved by the e2e suite

* add fixtures for the tests

* update cypress npm scripts to use concurrently

* add some e2e tests

frontend/cypress.json

@@ -0,0 +1,9 @@
+{
+  "integrationFolder": "cypress/integration",
+  "supportFile": "cypress/support/index.ts",
+  "videosFolder": "cypress/videos",
+  "screenshotsFolder": "cypress/screenshots",
+  "pluginsFile": "cypress/plugins/index.js",
+  "fixturesFolder": "cypress/fixtures",
+  "baseUrl": "http://localhost:4200"
+}