Removed PHPunit learning files

tests/EmailTest.php

@@ -1,27 +0,0 @@
-<?php declare(strict_types=1);
-use PHPUnit\Framework\TestCase;
-use MMK2410\MyTodoList\Email;
-
-final class EmailTest extends TestCase
-{
-    private $email = 'user@example.com';
-
-    public function testCanBeCreatedFromValidEmailAddress(): void {
-        $this->assertInstanceOf(
-            Email::class,
-            Email::fromString($this->email)
-        );
-    }
-
-    public function testCannotBeCreatedFromInvalidEmailAddress(): void {
-        $this->expectException(InvalidArgumentException::class);
-        Email::fromString('invalid');
-    }
-
-    public function testCanBeUsedAsString(): void {
-        $this->assertEquals(
-            $this->email,
-            Email::fromString($this->email)
-        );
-    }
-}