fix: Disable presigned without appropriate policy (#9621)

Fixes #9590

cmd/jwt.go

@@ -47,6 +47,7 @@ var (
 	errAuthentication       = errors.New("Authentication failed, check your access credentials")
 	errNoAuthToken          = errors.New("JWT token missing")
 	errIncorrectCreds       = errors.New("Current access key or secret key is incorrect")
+	errPresignedNotAllowed  = errors.New("Unable to generate shareable URL due to lack of read permissions")
 )
 
 func authenticateJWTUsers(accessKey, secretKey string, expiry time.Duration) (string, error) {