[EMCAL-1156] Modernize EMCal code and fix Digitizer

[mhemmer-cern]

Fix a bug in the Digitizer where iLabel was initialized at 0 and the incrementation in the loop was skipped due to always continue if the value is 0 without incrementing the value. Local testing showed that while it is clearly a logic bug, it did not effect MC production.

Modernize EMCal code: EMCALBase/Geometry and ClusterFactory Classes and DataFormatsEMCAL classes:

• Marking functions as no discard when the return type is not void
• Switching from gsl::span to std::span to use official stl container
• Removal of unused includes
• Ensuring initialization of all members
• Switching from C-style arrays to either std::array or std::span
• Removing else after return statements
• Merging of switch and if statements that had the same body
• In Cell.cxx add new function unpackV0 to unpack/decode the bitfields. Previously we just reinterpret_cast<const DecodingV0::CellDataPacked*> some const char* variable which violate type safety. Now it uses memcpy to safely copy the data from the buffer into the new DecodingV0::CellDataPacked object.

Fix return type for getCoreRadius (was bool should be float) and argument type for setUseWeightExotic(float useWeightExotic which should be setUseWeightExotic(bool useWeightExotic).

Removes streaming of spans from ROOT IO in ClusterFactory, since they are non owing spans.

Fixed some argument name differences between the definition and implementation of some functions.