fix: Fettling

Author: milesburton

.github/workflows/arduino_test_runner.yml

@@ -1,39 +1,34 @@
 name: Arduino CI
 
 on: [push, pull_request]
-
 jobs:
   test:
     runs-on: ubuntu-latest
-    
     steps:
       - uses: actions/checkout@v3
-      
       - name: Create required directories
         run: |
           mkdir -p $GITHUB_WORKSPACE/libraries
           mkdir -p $GITHUB_WORKSPACE/.arduino15
           mkdir -p $GITHUB_WORKSPACE/Arduino
-
       - name: Setup Arduino CLI
         uses: arduino/setup-arduino-cli@v1
-
       - name: Configure Arduino CLI
         run: |
           arduino-cli config init
           arduino-cli config set library.enable_unsafe_install true
           arduino-cli core update-index
+          arduino-cli config add board_manager.additional_urls https://arduino.esp8266.com/stable/package_esp8266com_index.json
+          arduino-cli core update-index
           arduino-cli core install arduino:avr
-        
+          arduino-cli core install esp8266:esp8266
       - name: Install OneWire library
         run: |
           arduino-cli lib install OneWire
-      
       - name: Set up Ruby
         uses: ruby/setup-ruby@v1
         with:
           ruby-version: '3.2.0'
-      
       - name: Install bundler
         run: |
           gem install bundler