build(docs-infra): support running cli docs examples concurrently (#29103)

PR Close #29103

aio/content/examples/component-interaction/example-config.json

@@ -4,7 +4,8 @@
       "cmd": "yarn",
       "args": [
         "e2e",
-        "--no-webdriver-update"
+        "--no-webdriver-update",
+        "--port={PORT}"
       ]
     }
   ]

aio/content/examples/dependency-injection/example-config.json

@@ -4,7 +4,8 @@
       "cmd": "yarn",
       "args": [
         "e2e",
-        "--no-webdriver-update"
+        "--no-webdriver-update",
+        "--port={PORT}"
       ]
     }
   ]

aio/content/examples/i18n/example-config.json

@@ -5,7 +5,8 @@
       "cmd": "yarn",
       "args": [
         "e2e",
-        "--no-webdriver-update"
+        "--no-webdriver-update",
+        "--port={PORT}"
       ]
     }
   ]

aio/content/examples/service-worker-getting-started/example-config.json

@@ -1,7 +1,7 @@
 {
   "projectType": "service-worker",
   "e2e": [
-    {"cmd": "yarn", "args": ["e2e", "--no-webdriver-update"]},
+    {"cmd": "yarn", "args": ["e2e", "--no-webdriver-update", "--port={PORT}"]},
     {"cmd": "yarn", "args": ["build", "--prod"]},
     {"cmd": "node", "args": ["--eval", "assert(fs.existsSync('./dist/ngsw.json'), 'ngsw.json is missing')"]},
     {"cmd": "node", "args": ["--eval", "assert(fs.existsSync('./dist/ngsw-worker.js'), 'ngsw-worker.js is missing')"]},