update test

Symfony changed the signature of their constructor when switching from `4.0` to `4.1`, which caused the tests to fail on the 'lowest' composer depenedencies.  This commit switches the test from using the `4.1` signature to the `4.0` signature so it passes for all users in the range of dependencies.  IMO, this was a BC break on Symfony's part that should never have happened, but we'll adjust to satisfy it.

symfony/http-foundation@4.0...4.1#diff-6c8d56052f6c60629eaaa4fca7887288L58

tests/Http/HttpUploadedFileTest.php

@@ -14,6 +14,7 @@ public function testUploadedFileCanRetrieveContentsFromTextFile()
             'test.txt',
             null,
             null,
+            null,
             true
         );