Fix clang tidy + remove warnings when building

[mcbarton]

@vgvassilev This is the PR to correct the bug introduced in clang tidy workflow in #269, found in vgvassilev/clad#883 . Once it is has been found to work in Clad this can be merged immediately.

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 75.45%. Comparing base (f93e7b6) to head (88ddb3e).
Report is 21 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main     #272       +/-   ##
===========================================
- Coverage   87.65%   75.45%   -12.21%     
===========================================
  Files           4        8        +4     
  Lines        1742     2994     +1252     
===========================================
+ Hits         1527     2259      +732     
- Misses        215      735      +520     

Files	Coverage Δ
lib/Interpreter/Compatibility.h	92.17% <ø> (-7.83%)	⬇️
lib/Interpreter/CppInterOp.cpp	82.14% <100.00%> (-5.06%)	⬇️
lib/Interpreter/DynamicLibraryManager.cpp	74.03% <100.00%> (ø)
lib/Interpreter/Paths.cpp	34.69% <100.00%> (ø)

... and 4 files with indirect coverage changes

Files	Coverage Δ
lib/Interpreter/Compatibility.h	92.17% <ø> (-7.83%)	⬇️
lib/Interpreter/CppInterOp.cpp	82.14% <100.00%> (-5.06%)	⬇️
lib/Interpreter/DynamicLibraryManager.cpp	74.03% <100.00%> (ø)
lib/Interpreter/Paths.cpp	34.69% <100.00%> (ø)

... and 4 files with indirect coverage changes