Fixed typo

Author: tristanbes

service_container/import.rst

@@ -104,7 +104,7 @@ current file or an absolute path.
 
 .. caution::
 
-   The imported files are loaded first; You should be carefull, because it can 
+   The imported files are loaded first; You should be careful, because it can 
    lead to some of your services definition to be overridden by rules present
    inside the file where you do imports