docs(@angular/cli): change default test watch flag (#13051)

Author: Mathou54

packages/angular/cli/lib/config/schema.json

@@ -1201,7 +1201,7 @@
             "watch": {
               "type": "boolean",
               "description": "Run build when files change.",
-              "default": false
+              "default": true
             },
             "poll": {
               "type": "number",