Adds deprecation notice to README.md #163

	name: .NET Library

	on:
	push:
	branches: [ main ]
	pull_request:
	branches: [ main, release ]

	jobs:
	build:
	name: Build and test
	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	os: [ windows-latest ] # Add other OSes later
	dotnet: ['3.1.x']

	steps:
	- name: Git Checkout
	uses: actions/checkout@v2
	with:
	submodules: recursive

	- name: Setup .NET
	uses: actions/setup-dotnet@v1
	with:
	dotnet-version: ${{ matrix.dotnet }}

	- name: Install dependencies
	run: dotnet restore
	- name: Install Codecov tool
	run: dotnet tool install --global Codecov.Tool --version 1.13.0
	- name: Build
	run: dotnet build --configuration Release --no-restore

	- name: Unit test & generate coverage report
	run: dotnet test Amazon.IonObjectMapper.Test /p:CollectCoverage=true /p:CoverletOutputFormat=opencover

	- name: Upload to Codecov
	uses: codecov/codecov-action@v1
	with:
	token: ${{ secrets.CODECOV_TOKEN }}
	flags: unittests

	- name: Performance test
	if: github.base_ref == 'release'
	run: dotnet test Amazon.IonObjectMapper.PerformanceTest

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