[Sigmon-765] Improve ramp-rate analysis in PCC.1 (80-120A)

What was done

• Ramp rate is analyzed only at specific intervals with steady increase/decrease of current.
• Zero crossing regions are excluded.

TODO

• In the future, change the analytic curve for 8 RPMC power converters (Agnieszka).
• Refactoring logic common to other projects for ramp-rate check.
• Refactoring d_dt method to pass window duration in ns as an argument.

QA

• Ran validation notebook over time period from 2020.01.01 till now.
• Out of 501 tests, 20 have an inconsistent result with the HWC summary. Inconsistency rate: 3.992%
• Out of 501 tests, 19 tests that used to be failing and are now passing (All of them SHOULD pass).
• Out of 501 tests, 1 tests that used to be passing and are now failing (as expected):

Recommissioning post LS2 - S23/S78 160368 RCBCH9.L3B2 PCC.1 2021-09-22 14:56:26.391 2021-09-22 15:06:11.378

Review objectives