Bumping deps - fixes highlight.php bug with php 7.3

Author: weaverryan

composer.json

@@ -13,7 +13,7 @@
         "ext-curl": "*",
         "doctrine/rst-parser": "dev-master",
         "guzzlehttp/guzzle": "~6.0",
-        "scrivo/highlight.php": "v9.12.0.5",
+        "scrivo/highlight.php": "^9.12.0",
         "symfony/filesystem": "^4.1",
         "symfony/finder": "^4.1",
         "symfony/dom-crawler": "^4.1",