Tweak bookmarklet

It’s strictly better to always explicitly use https:// (instead of protocol-relative URLs) for resources that are available over that protocol.

README.md

@@ -40,7 +40,7 @@ Browse it on your phone: [https://eruda.liriliri.io/](https://eruda.liriliri.io/
 In order to try it for different sites, execute the script below on browser address bar.
 
 ```javascript
-javascript:(function () { var script = document.createElement('script'); script.src="//cdn.jsdelivr.net/npm/eruda"; document.body.appendChild(script); script.onload = function () { eruda.init() } })();
+javascript:(function () { var script = document.createElement('script'); script.src="https://cdn.jsdelivr.net/npm/eruda"; document.body.append(script); script.onload = function () { eruda.init(); } })();
 ```
 
 ## Features
@@ -138,4 +138,4 @@ If you want to create a plugin yourself, follow the guides [here](./doc/PLUGIN.m
 
 ## Contribution
 
-Read [Contributing Guide](.github/CONTRIBUTING.md) for development setup instructions.
+Read [Contributing Guide](.github/CONTRIBUTING.md) for development setup instructions.