OSF: Used model.NewPointer everywhere (#27838)

```release-note
NONE
```

server/public/model/file_info.go

@@ -88,7 +88,7 @@ func (fi *FileInfo) PreSave() {
 	}
 
 	if fi.RemoteId == nil {
-		fi.RemoteId = NewString("")
+		fi.RemoteId = NewPointer("")
 	}
 }