Add d0,z0 electron variables

[dkobylianskii]

We missed these two variables in the preprocessing:

• ftag_z0AlongBeamspot
• d0RelativeToBeamspot

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 94.69%. Comparing base (41fa2a3) to head (2174b75). Report is 1 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #75 +/- ## ======================================= Coverage 94.69% 94.69% ======================================= Files 15 15 Lines 981 981 ======================================= Hits 929 929 Misses 52 52 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.