ITS/MFT digi: account BC reassignment in time wrt BC

Fix from @atriolo: In continuous mode, if mCollisionTimeWrtROF < 0, the reference BC is moved
one BC earlier to get the ROF ID it belongs to, but mCollisionTimeWrtROF is not increased by
24.95 ns to compensate for the shift of the reference BC: as a result the collision is placed
24.95 ns too early with respect to its ROF

Also ITS3 digitization is fixed.

Author: shahor02

Detectors/ITSMFT/common/simulation/src/Digitizer.cxx

@@ -158,8 +158,9 @@ void Digitizer::setEventTime(const o2::InteractionTimeRecord& irt, int layer)
   mCollisionTimeWrtROF = mEventTime.timeInBCNS; // in triggered mode the ROF starts at BC (is there a delay?)
   if (mParams.isContinuous()) {
     auto nbc = mEventTime.differenceInBC(mIRFirstSampledTF);
-    if (mCollisionTimeWrtROF < 0 && nbc > 0) {
-      nbc--;
+    if (mCollisionTimeWrtROF < 0. && nbc > 0) { // move to the ROF it actually belongs to and account
+      nbc--;                                    // this in the time offset wrt updated reference BC
+      mCollisionTimeWrtROF += o2::constants::lhc::LHCBunchSpacingNS;
     }
 
     // we might get interactions to digitize from before

Detectors/Upgrades/ITS3/simulation/src/Digitizer.cxx

@@ -123,8 +123,9 @@ void Digitizer::setEventTime(const o2::InteractionTimeRecord& irt, int layer)
   mCollisionTimeWrtROF = mEventTime.timeInBCNS; // in triggered mode the ROF starts at BC (is there a delay?)
   if (mParams.isContinuous()) {
     auto nbc = mEventTime.differenceInBC(mIRFirstSampledTF);
-    if (mCollisionTimeWrtROF < 0 && nbc > 0) {
-      nbc--;
+    if (mCollisionTimeWrtROF < 0. && nbc > 0) { // move to the ROF it actually belongs to and account
+      nbc--;                                    // this in the time offset wrt updated reference BC
+      mCollisionTimeWrtROF += o2::constants::lhc::LHCBunchSpacingNS;
     }
     // we might get interactions to digitize from before
     // the first sampled IR