Add name motivation

Author: eps1lon

docs/web-testing-library/faq.mdx

@@ -12,6 +12,7 @@ implementing the
 [Minimum Common Web Platform API](https://proposal-common-min-api.deno.dev/) (or
 parts of it). This includes browsers, Node.js, Deno, React Native and others
 (the [runtime keys](https://runtime-keys.proposal.wintercg.org/#react-native)
-contains known runtimes).
+contains known runtimes). The name is born out of pragmatism. A more precise
+name would be "Web-interoperable runtimes Testing Library".
 
 </details>