Remove PHP 5.x from composer.json, GitHub Actions

Author: stevegrunwell

.github/workflows/unit-tests.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        php-version: ['5.6', '7.0', '7.1', '7.2', '7.3', '7.4', '8.0', '8.1', '8.2', '8.3']
+        php-version: ['7.0', '7.1', '7.2', '7.3', '7.4', '8.0', '8.1', '8.2', '8.3']
     steps:
       - name: Checkout
         uses: actions/checkout@v4

composer.json

@@ -15,7 +15,7 @@
         "source": "https://github.com/stevegrunwell/phpunit-markup-assertions/"
     },
     "require": {
-        "php": "^5.6 || ^7.0 || ^8.0",
+        "php": "^7.0 || ^8.0",
         "symfony/css-selector": "^3.4|^4.4|^5.4|^6.0",
         "symfony/dom-crawler": "^3.4|^4.4|^5.4|^6.0"
     },