[SIGMON-734] PCC.1 (80-120A) with Savitzky-Golay and diff derivative methods

What was done

• Savitzky-Golay derivative method for voltage analysis (smoothing and differentiating voltage data, reducing noise while preserving features).
• Diff derivative method for plateau detection and current ramp-rate analysis.
• In addition, the time interval for the ramp-rate analysis is modified. If a valid plateau is not found, it is better to rely on the FGC PM timestamp instead of the beginning of the plateau when determining the time interval for the ramp-rate analysis (although the test will still fail because of the plateau).

QA

• Ran validation notebook over time period from 2020.01.01 till now.
• Out of 501 tests, 25 have an inconsistent result with the HWC summary. Inconsistency rate: 4.990%
• Out of 501 tests, 19 tests that used to be failing and are now passing (All of them SHOULD pass).
• Out of 501 tests, 6 tests that used to be passing and are now failing (As expected).