Make IndexError consistent

[ischoegl]

Changes proposed in this pull request

Minor follow-up to #1850. IndexError and ArraySizeError have different APIs (one uses max index and the other array size), where the former has the wrinkle that it won't work for empty arrays (with npos being a workaround). The update avoids having to call IndexError with array size - 1.

Checklist

• The pull request includes a clear description of this code change
• Commit messages have short titles and reference relevant issues
• Build passes (scons build & scons test) and unit tests address code coverage
• Style & formatting of contributed code follows contributing guidelines
• The pull request is ready for review

[codecov]

Codecov Report

Attention: Patch coverage is 35.00000% with 13 lines in your changes missing coverage. Please review.

Project coverage is 74.40%. Comparing base (fd1a410) to head (82329fc).

Files with missing lines	Patch %	Lines
src/equil/MultiPhase.cpp	0.00%	3 Missing ⚠️
src/base/ctexceptions.cpp	33.33%	1 Missing and 1 partial ⚠️
src/kinetics/Kinetics.cpp	33.33%	2 Missing ⚠️
include/cantera/base/Solution.h	0.00%	1 Missing ⚠️
include/cantera/oneD/Domain1D.h	50.00%	1 Missing ⚠️
include/cantera/oneD/OneDim.h	0.00%	1 Missing ⚠️
src/base/SolutionArray.cpp	0.00%	1 Missing ⚠️
src/thermo/Phase.cpp	50.00%	1 Missing ⚠️
src/zeroD/ReactorNet.cpp	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1851   +/-   ##
=======================================
  Coverage   74.40%   74.40%           
=======================================
  Files         386      386           
  Lines       53630    53630           
  Branches     9064     9064           
=======================================
  Hits        39905    39905           
  Misses      10653    10653           
  Partials     3072     3072           

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