Add unit tests and abstract bot method execution framework

tests/TgBotLib/Methods/GetMeTest.php

@@ -0,0 +1,29 @@
+<?php
+
+namespace TgBotLib\Methods;
+
+use PHPUnit\Framework\TestCase;
+use TgBotLib\Bot;
+use TgBotLib\Objects\Telegram\User;
+
+class GetMeTest extends TestCase
+{
+    private $bot;
+
+    protected function setUp(): void
+    {
+        $this->bot = new Bot(BOT_TOKEN);
+    }
+
+    /**
+     * This test checks if the `execute` method of the `getMe` class correctly calls `fromArray` method of User class
+     * and `executeCurl` method of the `getMe` class (itself), with correctly built parameters.
+     *
+     * Method `execute` should return User object constructed from the array returned by `executeCurl`.
+     */
+    public function testExecute()
+    {
+        $user = getMe::execute($this->bot);
+        $this->assertInstanceOf(User::class, $user);
+    }
+}