Properly show the number of interpolation points

Description

Properly show the number of interpolation points when initially loading the settings in the dock and also when switching between the different methods for the number of points (auto, etc.). Also, use the the information available in the columns statistics for the number of data points instead of calculating it in the dock widget.

Conformity

• Changelog entry
• Unit tests
• Update INSTALL
• Downport
• Fixes:

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When external dependencies are removed

• Reporting to ...