pgconf eu 2018 slides entry missing from https://wiki.postgresql.org/wiki/PostgreSQL_Related_Slides_and_Presentations

[Achilleas Mantzios]

Hello,

The pgconf eu 2018 entry is missing from 
https://wiki.postgresql.org/wiki/PostgreSQL_Related_Slides_and_Presentations 
.

I am afraid the more time passes since the event the harder to get 
people post their slides there, so pls update this ASAP.