added patches from framework to test php8 compatibility

composer.json

@@ -32,6 +32,7 @@
         "mailchimp/transactional": "^1.0.0"
     },
     "require-dev": {
+        "cweagans/composer-patches": "^1.7",
         "phpunit/phpunit": "4.8.34",
         "victorjonsson/markdowndocs": "*",
         "yiisoft/yii2-coding-standards": "~2.0"
@@ -45,5 +46,20 @@
         "psr-4": {
             "yiiunit\\extensions\\mandrill\\": "tests/"
         }
+    },
+    "extra": {
+        "branch-alias": {
+            "dev-master": "2.0.x-dev"
+        },
+        "composer-exit-on-patch-failure": false,
+        "patches": {
+            "phpunit/phpunit-mock-objects": {
+                "Fix PHP 7 and 8 compatibility": "https://yiisoft.github.io/phpunit-patches/phpunit_mock_objects.patch"
+            },
+            "phpunit/phpunit": {
+                "Fix PHP 7 compatibility": "https://yiisoft.github.io/phpunit-patches/phpunit_php7.patch",
+                "Fix PHP 8 compatibility": "https://yiisoft.github.io/phpunit-patches/phpunit_php8.patch"
+            }
+        }
     }
 }