Remove code deprecated in Cantera 2.4.0

[speth]

Remove code deprecated and marked for removal in Cantera 2.4. Includes the following classes: AxiStagnFlow and FreeFlame (now combined in StFlow), AqueousKinetics, Adsorbate, MetalSHEelectrons, MineralEQ3, MixedSolventElectrolyte, MolarityIonicVPSSTP, PhaseCombo_Interaction, LTPspecies, LiquidTranInteraction, LiquidTransport, LiquidTransportData, LiquidTransportParams, SimpleTransport, SolidTransport, SolidTransportData, Tortuosity.

Also adds new deprecations for some rarely-used functions defined in utilities.h, including sum_each, scatter_copy, sum_xlogx, etc.

[codecov]

Codecov Report

Merging #580 into master will increase coverage by 3.62%.
The diff coverage is 88%.

@@            Coverage Diff             @@
##           master     #580      +/-   ##
==========================================
+ Coverage   64.01%   67.63%   +3.62%     
==========================================
  Files         388      362      -26     
  Lines       41410    38390    -3020     
==========================================
- Hits        26507    25964     -543     
+ Misses      14903    12426    -2477

Impacted Files	Coverage Δ
include/cantera/transport/TransportBase.h	100% <ø> (ø)	⬆️
src/thermo/MultiSpeciesThermo.cpp	70.29% <ø> (+3.31%)	⬆️
include/cantera/kinetics/ThirdBodyCalc.h	100% <ø> (ø)	⬆️
src/thermo/MolalityVPSSTP.cpp	76.77% <ø> (+0.85%)	⬆️
include/cantera/thermo/LatticePhase.h	100% <ø> (ø)	⬆️
include/cantera/transport/WaterTransport.h	33.33% <ø> (ø)	⬆️
include/cantera/thermo/Phase.h	100% <ø> (ø)	⬆️
src/thermo/ThermoFactory.cpp	76.19% <ø> (-0.45%)	⬇️
src/thermo/ThermoPhase.cpp	65.75% <ø> (+1.03%)	⬆️
include/cantera/transport/TransportFactory.h	100% <ø> (ø)	⬆️
... and 30 more

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