item name positional placeholders not resolved in error/status messages

have an item that uses positional placeholders $1, $2 etc. export the host/template, import it - in the messages about created or updated items these placeholders are not resolved. as we resolve them everywhere else, they should be resolved in these messages, too

vaguely related to ZBXNEXT-1346, but as this is an inconsistency (and makes the messages way less useful), creating a new issue