📌 Exclude the new ReactNative preset from production builds

In #1193, I added
`module:@react-native/babel-preset`

That caused the unit tests to work, but caused a WSOD with the release build
e-mission/e-mission-docs#1113 (comment)

So we exclude the preset for production builds

I tried to add it only to dev builds, but the `process.env.ENV` is not set correctly
so I had to switch the condition
e-mission/e-mission-docs#1113 (comment)

Testing done:

```
$ npm run test

Test Suites: 27 passed, 27 total
Tests:       182 passed, 182 total
Snapshots:   0 total
Time:        10.537 s
Ran all test suites.
```

Author: shankari

babel.config.js

@@ -1,4 +1,14 @@
-module.exports = {
-  presets: ['@babel/preset-env', '@babel/preset-typescript', '@babel/preset-react', 'module:@react-native/babel-preset'],
-  plugins: ['@babel/plugin-transform-flow-strip-types'],
+module.exports = function(api) {
+    api.cache(true);
+    const presets = ['@babel/preset-env',
+        '@babel/preset-typescript',
+        '@babel/preset-react'];
+    const plugins = ['@babel/plugin-transform-flow-strip-types'];
+
+    if (process.env.ENV !== "production") {
+        presets.push('module:@react-native/babel-preset');
+    }
+    console.log("Running in environment "+process.env.ENV);
+
+    return {presets, plugins};
 }