py-fonttools: updated to 3.23.0

3.23.0:
[designspaceLib] Added an optional lib element to the designspace as a whole, as well as to the instance elements, to store arbitrary data in a property list dictionary, similar to the UFO窶冱 lib. Added an optional font attribute to the SourceDescriptor, to allow operating on in-memory font objects.
[cffLib] Fixed issue with lazy-loading of attributes when attempting to set the CFF TopDict.Encoding.
[ttx] Fixed regression introduced in 3.22.0 that affected the split tables -s option.
[feaLib] Added IncludedFeaNotFound custom exception subclass, raised when an included feature file cannot be found.
[otTables] Changed VarIdxMap to use glyph names internally instead of glyph indexes. The old ttx dumps of HVAR/VVAR tables that contain indexes can still be imported.
[varLib] Implemented VarStore optimizer.
[subset] Implemented pruning of GDEF VarStore, HVAR and MVAR.
[sfnt] Restore backward compatiblity with numFonts attribute of SFNTReader object.
[merge] Initial support for merging LangSysRecords.
[ttCollection] don窶冲 seek(0) when writing to possibly unseekable strems.
[subset] Keep all --name-IDs from 0 to 6 by default.
[cffLib] Added width module to calculate optimal CFF default and nominal glyph widths.
[varLib] Don窶冲 fail if STAT already in the master fonts

(adam)