Add LLVM/Clad 15 compatibility

[alexander-penev]

No description provided.

[codecov]

Codecov Report

Merging #514 (c98654b) into master (6250d7d) will increase coverage by 0.02%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #514      +/-   ##
==========================================
+ Coverage   92.45%   92.48%   +0.02%     
==========================================
  Files          37       39       +2     
  Lines        5556     5575      +19     
==========================================
+ Hits         5137     5156      +19     
  Misses        419      419              

Impacted Files	Coverage Δ
lib/Differentiator/DerivativeBuilder.cpp	100.00% <ø> (ø)
include/clad/Differentiator/Compatibility.h	89.47% <100.00%> (ø)
include/clad/Differentiator/VisitorBase.h	100.00% <100.00%> (ø)
lib/Differentiator/CladUtils.cpp	97.27% <100.00%> (+0.01%)	⬆️
lib/Differentiator/HessianModeVisitor.cpp	99.46% <100.00%> (ø)
lib/Differentiator/StmtClone.cpp	50.89% <100.00%> (ø)
lib/Differentiator/VisitorBase.cpp	97.63% <100.00%> (ø)
lib/Differentiator/EstimationModel.cpp	100.00% <0.00%> (ø)
include/clad/Differentiator/ErrorEstimator.h	100.00% <0.00%> (ø)
... and 5 more

Impacted Files	Coverage Δ
lib/Differentiator/DerivativeBuilder.cpp	100.00% <ø> (ø)
include/clad/Differentiator/Compatibility.h	89.47% <100.00%> (ø)
include/clad/Differentiator/VisitorBase.h	100.00% <100.00%> (ø)
lib/Differentiator/CladUtils.cpp	97.27% <100.00%> (+0.01%)	⬆️
lib/Differentiator/HessianModeVisitor.cpp	99.46% <100.00%> (ø)
lib/Differentiator/StmtClone.cpp	50.89% <100.00%> (ø)
lib/Differentiator/VisitorBase.cpp	97.63% <100.00%> (ø)
lib/Differentiator/EstimationModel.cpp	100.00% <0.00%> (ø)
include/clad/Differentiator/ErrorEstimator.h	100.00% <0.00%> (ø)
... and 5 more