Fix link to AWS-SDK credentials docs

Author: LevelbossMike

README.md

@@ -64,7 +64,7 @@ For detailed information on how configuration of plugins works, please refer to
 
 ### accessKeyId
 
-The AWS access key for the user that has the ability to upload to the `bucket`. If this is left undefined, the normal [AWS SDK credential resolution](7) will take place.
+The AWS access key for the user that has the ability to upload to the `bucket`. If this is left undefined, the normal [AWS SDK credential resolution][7] will take place.
 
 *Default:* `undefined`