Check 'Subresource Integrity' for external resources used by examples

[tbouffard]

We should do this for any styles or js resources not related to our project https://developer.mozilla.org/en-US/docs/Web/Security/Subresource_Integrity

See also https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/crossorigin

We will have do document how to generate the hash integrity value.

Notice that jsdelivr provide a way to retrieve a way to quickly get the hash and the html script directive (SRI related copied values in the following screenshots)

https://www.jsdelivr.com/package/npm/@kogito-tooling/kie-editors-standalone?path=dist%2Fbpmn

[tbouffard]

I have started applying this in #122 and #124