minor symfony#28337 [Filesystem] Use the real image URL for tests (sroze)

This PR was merged into the 2.8 branch.

Discussion
----------

[Filesystem] Use the real image URL for tests

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | ?
| Fixed tickets | ø
| License       | MIT
| Doc PR        | ø

AppVeyor is always failing on this test. Trying with the real HTTPS url of the image to see if it's working or if it's something else.

Commits
-------

886f739 Use the real image URL for the filesystem tests

Author: fabpot

src/Symfony/Component/Filesystem/Tests/FilesystemTest.php

@@ -161,7 +161,7 @@ public function testCopyCreatesTargetDirectoryIfItDoesNotExist()
      */
     public function testCopyForOriginUrlsAndExistingLocalFileDefaultsToCopy()
     {
-        $sourceFilePath = 'http://symfony.com/images/common/logo/logo_symfony_header.png';
+        $sourceFilePath = 'https://symfony.com/images/common/logo/logo_symfony_header.png';
         $targetFilePath = $this->workspace.\DIRECTORY_SEPARATOR.'copy_target_file';
 
         file_put_contents($targetFilePath, 'TARGET FILE');