Update NAVIGATE scenarios

[johannah-pik]

This PR includes an adjustment regarding the rate of direct electrification for trucks, busses and LDV 4 Wheelers for NAV_ele and NAV_all:

• Phase out of ICE LDV 4 Wheelers in the EU in 2035 (sales)
• Mix4 for ICE LDV 4 Wheelers globally
• Slightly more ambitious regarding direct electrification of Trucks and busses than Mix4