Bump crate version to 0.21.0 #144

	on:
	push:
	branches:
	- '**'
	pull_request:
	branches:
	- '**'
	schedule:
	# At 03:45 on Friday. (Thanks, crontab.guru)
	- cron: '45 3 * * 5'

	name: Build and test

	jobs:
	build_test:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	rust:
	- stable
	- beta
	- nightly
	fail-fast: false

	steps:
	- name: Checkout
	uses: actions/checkout@v4

	- name: Deploy toolchain
	uses: dtolnay/rust-toolchain@master
	with:
	toolchain: ${{ matrix.rust }}
	components: rustfmt, clippy

	- name: Run build
	run: cargo build --all-targets

	- name: Run tests
	run: cargo test

	- name: Check formatting
	run: cargo fmt --check

	- name: Run Clippy
	run: cargo clippy --all-targets

	- name: Run examples
	if: ${{ github.event_name != 'pull_request'}}
	env:
	HCLOUD_API_TOKEN: ${{ secrets.HCLOUD_API_TOKEN }}
	run: \|
	set -e
	cargo run --example find_cheapest_server_type "$HCLOUD_API_TOKEN"
	cargo run --example list_images "$HCLOUD_API_TOKEN"
	cargo run --example list_isos "$HCLOUD_API_TOKEN"
	cargo run --example list_servers "$HCLOUD_API_TOKEN"

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