Fix CellGroupConfig-related memory problems

This MR fixes multiple problems in the creation of the CellGroupConfig, that all originate in the fact that we reuse the structures of the SCC without properly copying them when using. This leads to the fact that when we do a reconfiguration, double-frees can ensue when freeing the CellGroupConfig, which might point to the SCC, hence (partially) freeing the SCC, up to multiple times attempting freeing the same memory.

After this MR, when the servingCellConfigDedicated is read correctly, we can initialize structures multiple UEs, which previously led to double-frees.