update carbon dep

Author: taylorotwell

composer.json

@@ -23,7 +23,7 @@
         "erusev/parsedown": "~1.6",
         "league/flysystem": "~1.0",
         "monolog/monolog": "~1.12",
-        "nesbot/carbon": "~1.20",
+        "nesbot/carbon": "~1.0",
         "psr/container": "~1.0",
         "psr/simple-cache": "^1.0",
         "ramsey/uuid": "^3.7",