s3: attempt to fix –s3-profile failing when explicit s3 endpoint is present FIXME DO NOT MERGE

This effectively reverts a fix so shouldn't be merged directly

backend/s3/s3.go

@@ -2657,7 +2657,7 @@ func s3Connection(ctx context.Context, opt *Options, client *http.Client) (*s3.S
 		}
 		// The session constructor (aws/session/mergeConfigSrcs) will only use the user's preferred credential source
 		// (from the shared config file) if the passed-in Options.Config.Credentials is nil.
-		awsSessionOpts.Config.Credentials = nil
+		// awsSessionOpts.Config.Credentials = nil
 	}
 	ses, err := session.NewSessionWithOptions(awsSessionOpts)
 	if err != nil {