Add new tests, remove redundant code

tests/SPC/store/DownloaderTest.php

@@ -0,0 +1,46 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SPC\Tests\store;
+
+use PHPUnit\Framework\TestCase;
+use SPC\store\Downloader;
+
+/**
+ * @internal
+ * TODO: Test all methods
+ */
+class DownloaderTest extends TestCase
+{
+    public function testGetLatestGithubTarball()
+    {
+        $this->assertEquals(
+            'https://api.github.com/repos/AOMediaCodec/libavif/tarball/v1.1.1',
+            Downloader::getLatestGithubTarball('libavif', [
+                'type' => 'ghtar',
+                'repo' => 'AOMediaCodec/libavif',
+            ])[0]
+        );
+    }
+
+    public function testDownloadGit() {}
+
+    public function testDownloadFile() {}
+
+    public function testLockSource() {}
+
+    public function testGetLatestBitbucketTag() {}
+
+    public function testGetLatestGithubRelease() {}
+
+    public function testCurlExec() {}
+
+    public function testCurlDown() {}
+
+    public function testDownloadSource() {}
+
+    public function testGetFromFileList() {}
+
+    public function testDownloadPackage() {}
+}