Update jsDelivr links

[LukasDrgon]

Hi this is Lukas from jsDelivr.

While our new back-end supports serving files from both npm and GitHub, we recommend always using only one of these methods for every package, with npm being the preferred one (using only npm means you can get detailed package usage statistics and npm packages are also searchable on our website).

I updated the links to use our npm endpoint. I also fixed one of the css links, because they we're pointing to the same file.

You can find links for all files at https://www.jsdelivr.com/package/npm/zebra_dialog.

Feel free to ping me if you have any questions regarding this change.

[stefangabos]

Thanks! I will update the other plugins also.