fix(object-storage): remove external link that adds no value

The concept has been explained before. Furthermore, it leads to a
Wikipedia page which, in this case, doesn't bring any valuable
information (`syntax` or `version` are not mentioned in this page).

Author: ahamez

pages/object-storage/api-cli/bucket-policy.mdx

@@ -44,7 +44,7 @@ Bucket policies use a JSON-based access policy language, and are composed of str
 ### Version
 
 **Description**
-: [IAM](https://en.wikipedia.org/wiki/Identity_management) syntax version
+: IAM syntax version
 
 **Required**
 : Yes