fix deprecation of `dtc` #648

	name: CI

	on:
	push:
	branches:
	- master
	pull_request:

	concurrency:
	# Skip intermediate builds: always.
	# Cancel intermediate builds: only if it is a pull request build.
	group: ${{ github.workflow }}-${{ github.ref }}
	cancel-in-progress: ${{ startsWith(github.ref, 'refs/pull/') }}

	jobs:
	test:
	name: Julia ${{ matrix.version }} - ${{ matrix.os }} - ${{ matrix.arch }} - ${{ github.event_name }}
	runs-on: ${{ matrix.os }}
	continue-on-error: ${{ matrix.version == 'nightly' }}
	strategy:
	fail-fast: false
	matrix:
	version:
	- '1'
	- '1.6'
	- 'nightly'
	os:
	- ubuntu-latest
	arch:
	- x64
	include:
	- version: 1
	os: macOS-latest
	arch: x64
	- version: 1
	os: windows-latest
	arch: x64
	steps:
	- uses: actions/checkout@v2
	- uses: julia-actions/setup-julia@v1
	with:
	version: ${{ matrix.version }}
	arch: ${{ matrix.arch }}
	- uses: actions/cache@v1
	env:
	cache-name: cache-artifacts
	with:
	path: ~/.julia/artifacts
	key: ${{ runner.os }}-test-${{ env.cache-name }}-${{ hashFiles('**/Project.toml') }}
	restore-keys: \|
	${{ runner.os }}-test-${{ env.cache-name }}-
	${{ runner.os }}-test-
	${{ runner.os }}-
	- uses: julia-actions/julia-buildpkg@v1
	- uses: julia-actions/julia-runtest@v1
	with:
	coverage: ${{ matrix.version == '1' && matrix.os == 'ubuntu-latest' }}
	env:
	GROUP: AbstractGPs
	- uses: julia-actions/julia-processcoverage@v1
	if: matrix.version == '1' && matrix.os == 'ubuntu-latest'
	- name: Send coverage
	if: matrix.version == '1' && matrix.os == 'ubuntu-latest'
	uses: codecov/codecov-action@v1
	with:
	file: lcov.info

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