Add new Discourse forum badge to `README` #4359

	name: Test
	on: [push, pull_request]
	jobs:
	native:
	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	os: [ubuntu-latest, windows-latest, macOS-latest]
	rust: [stable, beta]
	steps:
	- uses: hecrj/setup-rust-action@v1
	with:
	rust-version: ${{ matrix.rust }}
	- uses: actions/checkout@master
	- name: Install dependencies
	if: matrix.os == 'ubuntu-latest'
	run: \|
	export DEBIAN_FRONTED=noninteractive
	sudo apt-get -qq update
	sudo apt-get install -y libxkbcommon-dev
	- name: Run tests
	run: \|
	cargo test --verbose --workspace
	cargo test --verbose --workspace --all-features

	web:
	runs-on: ubuntu-latest
	steps:
	- uses: hecrj/setup-rust-action@v1
	with:
	rust-version: stable
	targets: wasm32-unknown-unknown
	- uses: actions/checkout@master
	- name: Run checks
	run: cargo check --package iced --target wasm32-unknown-unknown
	- name: Check compilation of `tour` example
	run: cargo build --package tour --target wasm32-unknown-unknown
	- name: Check compilation of `todos` example
	run: cargo build --package todos --target wasm32-unknown-unknown
	- name: Check compilation of `integration` example
	run: cargo build --package integration --target wasm32-unknown-unknown

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