Link output element queries for transport final demand per carrier to queries in general folder

[kndehaan]

Description

In this PR, transport final demand per carrier queries for passenger transport were added in the general query folder. It would be desirable to have these queries for all transport modi in the general folder and have output element queries refer to queries in the general folder, which is currently not the case.

This is a nice-to-have for #3372

Proposed Improvement

The general query folder should contain queries for final demand per carrier per transport modi. This means that:

• Queries still need to be added to the general folder for domestic aviation, freight transport (queries for domestic navigation are already present) and international transport.
• The queries in the general folder should have the same unit, being PJ
• Output element queries should refer to queries from the general folder