ci: fix not running tests

Author: JanTvrdik

composer.json

@@ -53,6 +53,7 @@
             "@check:composer",
             "@check:cs",
             "@check:types",
+            "@check:tests",
             "@check:dependencies",
             "@check:collisions"
         ],
@@ -63,6 +64,7 @@
         ],
         "check:cs": "phpcs",
         "check:dependencies": "composer-dependency-analyser",
+        "check:tests": "phpunit -vvv tests",
         "check:types": "phpstan analyse -vv --ansi",
         "fix:cs": "phpcbf"
     }