Add CI workflow to do Arduino project-specific linting

On every push, pull request, and periodically, run Arduino Lint to check for common problems not related to the project
code.

Author: per1234

.github/workflows/check-arduino.yml

@@ -0,0 +1,28 @@
+name: Check Arduino
+
+# See: https://docs.github.com/en/free-pro-team@latest/actions/reference/events-that-trigger-workflows
+on:
+  push:
+  pull_request:
+  schedule:
+    # Run every Tuesday at 8 AM UTC to catch breakage caused by new rules added to Arduino Lint.
+    - cron: "0 8 * * TUE"
+  workflow_dispatch:
+  repository_dispatch:
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Arduino Lint
+        uses: arduino/arduino-lint-action@v1
+        with:
+          compliance: specification
+          library-manager: update
+          # Always use this setting for official repositories. Remove for 3rd party projects.
+          official: true
+          project-type: library

README.md

@@ -1,5 +1,6 @@
 # ArduinoMotorCarrier library
 
+[![Check Arduino status](https://github.com/arduino-libraries/ArduinoMotorCarrier/actions/workflows/check-arduino.yml/badge.svg)](https://github.com/arduino-libraries/ArduinoMotorCarrier/actions/workflows/check-arduino.yml)
 [![Spell Check status](https://github.com/arduino-libraries/ArduinoMotorCarrier/actions/workflows/spell-check.yml/badge.svg)](https://github.com/arduino-libraries/ArduinoMotorCarrier/actions/workflows/spell-check.yml)
 
 This library is designed to use the MKR Motor Carrier. The shield supports micro servo motors, DC motors and DC motors with encoder. This library, therefore, has functions and creates objects to support such hardware. Objects are automatically created when "ArduinoMotorCarrier.h" is included, hence no need to initiate objects manually.