set php version

.github/workflows/test.yml

@@ -12,10 +12,11 @@ jobs:
                 phpunit-versions: [ 'latest' ]
         steps:
             -   uses: actions/checkout@v1
+
             -   name: Setup PHP
                 uses: shivammathur/setup-php@v2
                 with:
-                    php-version: '8.0'
+                    php-version: '${{ matrix.php-versions }}'
 
             -   name: Validate composer.json and composer.lock
                 run: composer validate

composer.json

@@ -29,10 +29,15 @@
         "ext-curl": "*",
         "guzzlehttp/guzzle": "~6.0 || ~7.0",
         "ext-json": "*",
-        "beberlei/assert": "^3.3"
+        "beberlei/assert": "^2.9.9"
+    },
+    "config": {
+        "platform": {
+            "php": "5.6"
+        }
     },
     "require-dev": {
-        "phpunit/phpunit": "^9"
+        "phpunit/phpunit": "^5.7.27"
     },
     "support": {
         "email": "[email protected]"