remove gps_time

[vuillaut]

gps time is not used anywhere and is now written as nan value in dl1, causing errors down the line.

Same error can get caused by mc_core_distance filled by nan

[codecov]

Codecov Report

Merging #493 into lstchain_ctapipe0.8 will decrease coverage by 0.01%.
The diff coverage is 100.00%.

@@                   Coverage Diff                   @@
##           lstchain_ctapipe0.8     #493      +/-   ##
=======================================================
- Coverage                41.61%   41.59%   -0.02%     
=======================================================
  Files                       77       77              
  Lines                     6430     6428       -2     
=======================================================
- Hits                      2676     2674       -2     
  Misses                    3754     3754              

Impacted Files	Coverage Δ
lstchain/reco/r0_to_dl1.py	64.96% <ø> (-0.12%)	⬇️
lstchain/io/lstcontainers.py	87.81% <100.00%> (-0.07%)	⬇️

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[tysaito2008]

thank you for removing it. It was just confusing.

[andres-baquero]

I have tested the changes running lstchain_dl1_to_dl2.py and it is running well.

[vuillaut]

I have tested the changes running lstchain_dl1_to_dl2.py and it is running well.

Thank you for the test and review