refactor #32 Initialize Github Actions (clem21, Zales0123)

This PR was merged into the 4.0-dev branch.

Discussion
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Commits
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66b62a4 Initialize Github Actions
c1a96a1 Modify and simplify workflow file

Author: GSadee

.github/workflows/build.yml

@@ -0,0 +1,65 @@
+name: Build
+
+on:
+  push: ~
+  pull_request: ~
+  release:
+    types: [created]
+  schedule:
+    -
+      cron: "0 1 * * 6" # Run at 1am every Saturday
+
+jobs:
+  tests:
+    runs-on: ubuntu-latest
+
+    name: "PHP ${{ matrix.php }}, ECS ${{ matrix.ecs }}"
+
+    strategy:
+      fail-fast: false
+      matrix:
+        php: [7.4, 7.3]
+        ecs: [9.*, 8.*]
+
+    steps:
+      -
+        uses: actions/checkout@v2
+
+      -
+        name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: "${{ matrix.php }}"
+          extensions: intl
+          tools: symfony
+          coverage: none
+
+      -
+        name: Get Composer cache directory
+        id: composer-cache
+        run: echo "::set-output name=dir::$(composer config cache-files-dir)"
+
+      -
+        name: Cache Composer
+        uses: actions/cache@v2
+        with:
+          path: ${{ steps.composer-cache.outputs.dir }}
+          key: ${{ runner.os }}-php-${{ matrix.php }}-composer-${{ hashFiles('**/composer.json **/composer.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-php-${{ matrix.php }}-composer-
+
+      -
+        name: Require EasyCodingStandard version
+        run: composer require symplify/easy-coding-standard:${{ matrix.ecs }} --no-update --no-scripts
+
+      -
+        name: Install PHP dependencies
+        run: composer install --no-interaction
+
+      -
+        name: Validate composer.json
+        run: composer validate --ansi --strict
+
+      -
+        name: Run test
+        run: vendor/bin/ecs check --config ecs.php tests ecs.php