[MUON] added option for storing nCandidates in the MFT-MCH matching

The number of candidates to be stored is specified in the
`MUON_MATCHING_NCANDIDATES` environment variable.

By default the variable is not set, and no option is passed to the global
forward matching workflow for storing multiple candidates.

Hence the default behaviour of the forward matching is unchanged.

Author: aferrero2707

DATA/common/setenv.sh

@@ -169,6 +169,9 @@ ITSMFT_STROBES=""
 [[ ! -z ${ITS_STROBE:-} ]] && ITSMFT_STROBES+="ITSAlpideParam.roFrameLengthInBC=$ITS_STROBE;"
 [[ ! -z ${MFT_STROBE:-} ]] && ITSMFT_STROBES+="MFTAlpideParam.roFrameLengthInBC=$MFT_STROBE;"
 
+MFTMCH_NCANDIDATES_OPT=
+[[ ! -z ${MUON_MATCHING_NCANDIDATES:-} ]] && MFTMCH_NCANDIDATES_OPT+="FwdMatching.saveMode=3;FwdMatching.nCandidates=${MUON_MATCHING_NCANDIDATES};"
+
 
 # Set active reconstruction steps (defaults added according to SYNCMODE)
 for i in `echo $LIST_OF_GLORECO | sed "s/,/ /g"`; do