minor #4122 DX: AppVeyor - Update Composer download link (SpacePossum)

This PR was squashed before being merged into the 2.12 branch (closes #4122).

Discussion
----------

DX: AppVeyor - Update Composer download link

check if it helps for this:
 https://ci.appveyor.com/project/keradus/php-cs-fixer/builds/20581477/job/pfs3dwem99hkm4hg

Commits
-------

5148eb8f DX: AppVeyor - Update Composer download link

.appveyor.yml

@@ -29,7 +29,7 @@ install:
     - echo extension=php_curl.dll >> php.ini
     - echo extension=php_openssl.dll >> php.ini
     - echo extension=php_mbstring.dll >> php.ini
-    - IF NOT EXIST C:\tools\composer.phar (cd C:\tools && appveyor DownloadFile https://getcomposer.org/download/1.4.1/composer.phar)
+    - IF NOT EXIST C:\tools\composer.phar (cd C:\tools && appveyor DownloadFile https://getcomposer.org/composer.phar)
     - cd C:\projects\php-cs-fixer
     - php C:\tools\composer.phar global show hirak/prestissimo -q || php C:\tools\composer.phar global require hirak/prestissimo