feat(composer): allow usage of php ^7.2.5

composer.json

@@ -5,7 +5,7 @@
     "prefer-stable": true,
     "minimum-stability": "dev",
     "require": {
-        "php": "^8.0",
+        "php": "^7.2.5||^8.0",
         "picocms/pico": "dev-fix-compatibility-php8 as v3.0.0-alpha.2",
         "seacms/app": "dev-master",
         "seacms/seacms-theme": "dev-master"
@@ -13,7 +13,7 @@
     "config": {
         "optimize-autoloader": true,
         "platform": {
-            "php": "8.0.0"
+            "php": "7.2.5"
         },
         "platform-check": true,
         "sort-packages": true,
@@ -70,6 +70,6 @@
         }
     },
     "require-dev": {
-        "phpunit/phpunit": "^9.6"
+        "phpunit/phpunit": "^8.5"
     }
 }