Enable the jsx-runtime plugin for vite's ESLint

This prevents it complaining about a missing React import.

Enabling this is recommended by the vite starter itself:

> Install
  [eslint-plugin-react](https://github.com/jsx-eslint/eslint-plugin-react) and
  add `plugin:react/recommended` & `plugin:react/jsx-runtime` to the `extends`
  list

web/packages/build-config/eslintrc-vite.js

@@ -1,5 +1,5 @@
 /* eslint-env node */
 module.exports = {
-    extends: ["./eslintrc-react.js"],
+    extends: ["./eslintrc-react.js", "plugin:react/jsx-runtime"],
     ignorePatterns: [".eslintrc.cjs", "vite.config.ts", "dist"],
 };