[AGIPD][CS] Correction using Current source slopes

Description

Adding AGIPD Correction using Current Source calibration developed at : !874 (merged)

The main purpose is to replace PC correction with CS correction. So for now we leave PC but we either apply CS or PC and never both at the same time.

• Integration time is not used with CS constants
• For baseline corrections (blc_strips, blc_hmatch, and blc_noise) and metl_snow use SlopesPC if rel_gain is off. Otherwise, use the retrieved constant selected for relative gain (PC or CS).

- [ ] Have one parameter instead of 2: switch rel_gain from boolean to string parameter. Will leave this point for later

❗ I have decided on splitting the required change for AGIPD CS correction into two steps:

• This current branch introduces a new string-valued rel_gain_mode parameter.
• The next change will be about replacing and converting the boolean rel_gain with the string value rel_gain_mode, to have one parameter only.

The reason is that converting rel_gain will require more changes for updated_config, test_update_config, test_reference_runs, and all YAML configurations in calibration_configurations

How Has This Been Tested?

• unit tests

Relevant Documents (optional)

CS with mg adjust: AGIPD_CORRECT_CS_adjust_mg.pdf

CS: AGIPD_CORRECT_CS.pdf

PC: AGIPD_CORRECT_PC.pdf

PC with no mg adjust: AGIPD_CORRECT_PC_no_adjust_mg.pdf

Types of changes

• New feature (non-breaking change which adds functionality)

Checklist:

Reviewers

@rovensky @jsztuk @schmidtp @hammerd @kluyvert