fix[pallas-math]: use malachite as default #1478

	# Based on https://github.com/actions-rs/meta/blob/master/recipes/quickstart.md

	on:
	push: { }

	name: Validate

	jobs:
	check:
	name: Check
	strategy:
	fail-fast: false
	matrix:
	os: [ windows-latest, ubuntu-latest, macOS-latest ]
	rust: [ stable ]

	runs-on: ${{ matrix.os }}

	steps:
	- name: Checkout sources
	uses: actions/checkout@v2

	- name: Install stable toolchain
	uses: dtolnay/rust-toolchain@stable
	with:
	toolchain: ${{ matrix.rust }}

	- name: Run cargo check Windows
	if: matrix.os == 'windows-latest'
	run: cargo check

	- name: Run cargo check
	if: matrix.os != 'windows-latest'
	run: cargo check --features gmp

	test:
	name: Test Suite
	runs-on: ubuntu-latest
	steps:
	- name: Checkout sources
	uses: actions/checkout@v2

	- name: Install stable toolchain
	uses: dtolnay/rust-toolchain@stable
	with:
	toolchain: stable

	- name: Run cargo test
	run: cargo test --features gmp

	test-windows:
	name: Test Suite Windows
	runs-on: windows-latest
	steps:
	- name: Checkout sources
	uses: actions/checkout@v2

	- name: Install stable toolchain
	uses: dtolnay/rust-toolchain@stable
	with:
	toolchain: stable

	- name: Run cargo test
	run: cargo test

	lints:
	name: Lints
	runs-on: ubuntu-latest
	steps:
	- name: Checkout sources
	uses: actions/checkout@v2

	- name: Install stable toolchain
	uses: dtolnay/rust-toolchain@stable
	with:
	toolchain: stable
	components: rustfmt, clippy

	- name: Run cargo fmt
	run: cargo fmt --all -- --check

	- name: Run cargo clippy
	run: \|
	cargo clippy -- -D warnings
	cargo clippy --features gmp -- -D warnings

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