ATLASRECTS-7334: check if the matrix is invertiable before inverting it
As discussed in https://its.cern.ch/jira/browse/ATLASRECTS-7334, this MR will fix the FPEs in the KalmanVertexTrackUpdator by checking if the matrix is invertiable before inversing it. Ping @kostyuk and @jburzyns .
Edited by Christos Anastopoulos