TPC_MC_anchoring_simple: Added per region relative gas gain to simulate the change in the voltage settings of GEMs

[tubagundem]

Added per region (IROC, OROC1, OROC2, OROC3) relative gas gain to the effective mode of amplification process by simply scaling the outcome of the amplification process. This is done to simulate the change in voltage settings of GEMs in 2024 and 2025.

[github-actions[bot]]

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