Add vendor and .env to make usable

vendor/phpunit/php-code-coverage/tests/_files/CoverageMethodOneLineAnnotationTest.php

@@ -0,0 +1,12 @@
+<?php
+use PHPUnit\Framework\TestCase;
+
+class CoverageMethodOneLineAnnotationTest extends TestCase
+{
+    /** @covers CoveredClass::publicMethod */
+    public function testSomething()
+    {
+        $o = new CoveredClass;
+        $o->publicMethod();
+    }
+}