Make progress bar optional and add it also to DL2 script

[HealthyPear]

In the case of a finite number of shower events, the GRID was killing the jobs due to the ASCII characters of the progress bar.

[codecov]

Codecov Report

Merging #154 (de588cc) into master (2fe78fc) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #154      +/-   ##
==========================================
+ Coverage   66.81%   66.84%   +0.02%     
==========================================
  Files          23       23              
  Lines        2242     2244       +2     
==========================================
+ Hits         1498     1500       +2     
  Misses        744      744              

Impacted Files	Coverage Δ
protopipe/scripts/data_training.py	93.08% <100.00%> (+0.03%)	⬆️
protopipe/scripts/write_dl2.py	82.02% <100.00%> (+0.05%)	⬆️

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