Fix missing values in final metrics generated

[kareefardi]

trafficstars

• Script was trying to fetch values from wrong paths. Paths are corrected to nom corner. These are the fixed metrics:

  • Power values
  • critical_path_report
  • some wns and tns values
  • klayout drc
  • remove cvc values

• Add sandbox to git ignore for development reasons

• Update benchmark results to remove cvc values column

Fixes https://github.com/The-OpenROAD-Project/OpenLane/issues/2125