build(docs-infra): use puppeteer to get a browser for docs examples tests (#35381)

In #35049, integration and AIO tests were changed to use the browser
provided by `puppeteer` in tests. This commit switches the docs examples
tests to use the same setup.

IMPLEMENTATION NOTE:
The examples are used to create ZIP archives that docs users can
download to experiment with. Since we want the downloaded projects to
resemble an `@angular/cli` generated project, we do not want to affect
the project's Protractor configuration in order to use `puppeteer`.

To achieve this, a second Protractor configuration is created (which is
ignored when creating the ZIP archives) that extends the original one
and passes the approperiate arguments to use the browser provided by
`puppeteer`. This new configuration (`protractor-puppeteer.conf.js`) is
used when running the docs examples tests (on CI or locally during
development).

PR Close #35381

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

@@ -4,9 +4,10 @@
       "cmd": "yarn",
       "args": [
         "e2e",
+        "--protractor-config=e2e/protractor-puppeteer.conf.js",
         "--no-webdriver-update",
         "--port={PORT}"
       ]
     }
   ]
-}
+}

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

@@ -4,9 +4,10 @@
       "cmd": "yarn",
       "args": [
         "e2e",
+        "--protractor-config=e2e/protractor-puppeteer.conf.js",
         "--no-webdriver-update",
         "--port={PORT}"
       ]
     }
   ]
-}
+}

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

@@ -5,9 +5,10 @@
       "cmd": "yarn",
       "args": [
         "e2e",
+        "--protractor-config=e2e/protractor-puppeteer.conf.js",
         "--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", "--port={PORT}"]},
+    {"cmd": "yarn", "args": ["e2e", "--protractor-config=e2e/protractor-puppeteer.conf.js", "--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')"]},