Ensure compatibility with dplyr > 1.1.0

[Veerle van Leemput]

Prevent the following warning message when running the process_e4 function:

Caused by warning:
! Using `across()` without supplying `.cols` was deprecated in dplyr
  1.1.0.
ℹ Please supply `.cols` instead.

It's coming from this function: compute_features2