Consolidated issue cataloguing all Fetch/HTTP issues with test harness

## Bug Report

### Capacitor Version
`4.6.1`

### Platform(s)
Android / iOS

### Code Reproduction
I took the time to put together a test harness that reproduces all the issues HTTP/Fetch has right now on iOS and Android. There may be others, but this is what I've seen so far.

Go to https://github.com/silviogutierrez/capacitor-http-tester and clone the repository.

Run `npm install` and `npm cap sync` to get both emulators working.

Then run `npm run build && node server.js` to start the local server.

Now open `http://localhost:3000` and see how everything works on the browser.

After that run `npx cap open ios` and run the simulator. And `npx cap open android` and run the emulator. You'll see what's failing and what's not.

I've tried to associate the bugs with the issue number.

Hopefully this is helpful.

Related issues: #6174, #5945, #6165, #6142, #6170, #6126 #6196 #6197