Remove code duplication in payload inspector code for timing calibration

[grzanka]

We have a lot of automatically generated duplicated code in payload inspector, in module responsible for timing calibration history plotting.

See for example the code:
https://github.com/cms-sw/cmssw/blob/bbbd24b6d34cadb04284c36ee78f88c4bf944670/CondCore/CTPPSPlugins/plugins/PPSTimingCalibration_PayloadInspector.cc#L17

This code was merged in following PR:
https://github.com/cms-sw/cmssw/pull/39024/files
where more than 3500 automatically generated code lines were added.

This code allows user to select proper plot of conditions history for any combination of following parameters: db (0,1), plane (0,1,2,3), channel (0,1,2,...11) and param (0,1,2,3). This gives 384 possible combinations if I am not mistaken. Proper combination can be selected by the user from dropdown list as seen below:

We are curious if there is a smarter way (with much smaller code base) to achieve similar functionality.
There is a parametrized plot as seen below:

The question is whether it is possible to have plots parametrized and the parameter are limited to certain values (for example by using dropdown lists).

[grzanka]

@Kszemka FYI