Use different ports for start-prod and start-examples (#5592)

Because the production build uses a service worker, it can be annoying
to have that service worker be installed on localhost:4242 and then not
see your changes when you switch to the development build.

Use port 4243 for start-prod and start-l10n-prod, and use port 4244 for
start-examples.

Author: mstange

package.json

@@ -34,12 +34,12 @@
     "license-check": "devtools-license-check",
     "preinstall": "node bin/pre-install.js",
     "publish": "rimraf public_html && cp -r dist public_html",
-    "serve-static": "ws -d dist/ -s index.html -p 4242",
+    "serve-static": "ws -d dist/ -s index.html -p 4243",
     "start": "yarn build:clean && cross-env NODE_ENV=development node server.js",
     "start-prod": "yarn build-prod && yarn serve-static",
     "start-l10n": "yarn build:clean && cross-env NODE_ENV=development L10N=1 node server.js",
     "start-l10n-prod": "yarn build-l10n-prod && yarn serve-static",
-    "start-examples": "ws -d examples/ -s index.html -p 4242",
+    "start-examples": "ws -d examples/ -s index.html -p 4244",
     "start-docs": "ws -d docs-user/ -p 3000",
     "start-photon": "node res/photon/server",
     "test": "node bin/output-fixing-commands.js cross-env LC_ALL=C TZ=UTC NODE_ENV=test jest",