Optimization of the FlashFinder algorithm

[CarlosNeutrino]

Description

• This PR includes small changes in the FlashFinder algorithm
• It includes the possibility of creating a shortened OpFlash when a flash candidate occurs before an already defined OpFlash
• The time between the shortened OpFlash and the later one has to be at least of 0.5μs
• The time-width of the flashes is saved as an attribute to the recob::OpFlash class. Its value will be 4μs for non-shortened flash and a smaller value for the newly added flashes
• The modules that are affected are reco1:opflashtpc0:SBNDFlashFinder and reco1:opflashtpc1:SBNDFlashFinder
• Details and validation plots can be found in the linked docdb

Link(s) to docdb describing changes (optional)

Link of the docdb describing the changes: docdb-46414

Relevant PR links (optional)

This PR does not require merging another PR before

Development

• This PR raises this different issue on the OptT0 calculation: Issue-638

This PR

Checklist

• Added at least 1 label from available labels.
• Assigned at least 1 reviewer under Reviewers,
• Assigned all contributers including yourself under Assignees
• Linked any relevant issues under Developement
• Does this PR affect CAF data format? If so, please assign a CAF maintainer (PetrilloAtWork or JosiePaton) as additional reviewer.
• Does this affect the standard workflow?
• Is this PR a patch for the ongoing production? If so, separate PR must also be made for production/v10_06_00 branch!