Update CONTRIBUTING.md document across our repositories

## Description

We have updated our `CONTRIBUTING.md` document in https://github.com/apache/cordova-contribute/pull/37. Those changes need to be added to our other repositories, too:

## Implementation Progress

### Platforms

- [ ] cordova-android
- [ ] cordova-browser
- [ ] cordova-electron
- [ ] cordova-ios
- [ ] cordova-osx
- [ ] cordova-test-platform
- [ ] cordova-windows

### Plugins

- [ ] cordova-plugin-battery-status
- [ ] cordova-plugin-camera
- [ ] cordova-plugin-device
- [ ] cordova-plugin-dialogs
- [ ] cordova-plugin-file
- [ ] cordova-plugin-geolocation
- [ ] cordova-plugin-inappbrowser
- [ ] cordova-plugin-media
- [ ] cordova-plugin-media-capture
- [ ] cordova-plugin-network-information
- [ ] cordova-plugin-screen-orientation
- [ ] cordova-plugin-splashscreen
- [ ] cordova-plugin-statusbar
- [ ] cordova-plugin-vibration
- [ ] cordova-plugin-whitelist
- [ ] cordova-plugin-wkwebview-engine

### Tooling

- [ ] cordova-cli
- [ ] cordova-coho
- [ ] cordova-common
- [ ] cordova-create
- [ ] cordova-docs
- [ ] cordova-fetch
- [ ] cordova-js
- [ ] cordova-lib
- [ ] cordova-mobile-spec
- [ ] cordova-node-xcode
- [ ] cordova-paramedic
- [ ] cordova-plugin-test-framework
- [ ] cordova-plugman
- [ ] cordova-serve

### Misc

- [ ] cordova
- [ ] cordova-app-hello-world

**Excluded:**
- cordova-status

and any unused, outdated, or deprecated repos.