Use fixed version of expressif library to prevent linker error. #30

	name: PlatformIO CI

	# Controls when the action will run. Triggers the workflow on push or pull request
	# events but only for the master branch
	on: [push, pull_request]

	# A workflow run is made up of one or more jobs that can run sequentially or in parallel
	jobs:
	# This workflow contains a single job called "build"
	build:
	# The type of runner that the job will run on
	runs-on: ubuntu-latest
	strategy:
	matrix:
	example: [examples/demo-sensor-nodes.cpp, examples/demo-relay-contact-nodes.cpp, examples/demo-pulse-node.cpp, examples/demo-ping-node.cpp]

	# Steps represent a sequence of tasks that will be executed as part of the job
	steps:
	# Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
	- uses: actions/checkout@v2

	- name: Set up Python
	uses: actions/setup-python@v1

	- name: Install pio and its dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install platformio

	- name: Install Arduino Core for ESP8266
	run: pio platform install espressif8266

	- name: Install Arduino Core for ESP32
	run: pio platform install espressif32

	- name: Install current code as a PlatformIO library with all dependencies
	run: pio lib -g install file://.

	- name: Run PlatformIO CI
	# run: pio ci --board=esp01_1m --board=d1_mini
	run: pio ci --project-conf=platformio.ini
	env:
	PLATFORMIO_CI_SRC: ${{ matrix.example }}

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