package.json: bump eslint to ^8.0.0 and all eslint-x dependencies

So as to satisfy the new eslint peer dependency.

In addition drop eslint-config-standard-react as it does not release
anymore, and eslint 8.x is not compatible with the available last
release.
https://github.com/standard/eslint-config-standard-react/pull/69

Replace it with https://github.com/facebook/create-react-app#readme
which is actively maintained.

Lastly drop the deprecated
https://github.com/standard/eslint-plugin-standard

.eslintrc.json

@@ -4,7 +4,7 @@
         "browser": true,
         "es6": true
     },
-    "extends": ["eslint:recommended", "standard", "standard-jsx", "standard-react"],
+    "extends": ["eslint:recommended", "standard", "standard-jsx", "react-app"],
     "parser": "@babel/eslint-parser",
     "parserOptions": {
         "ecmaVersion": "7",