fix type system when a record's field is an alias type

[quentin]

Fix the type system when a record's field is an alias type.
Added a test.

[codecov]

Codecov Report

Merging #2219 (604e2aa) into master (f16d18d) will decrease coverage by 0.26%.
The diff coverage is 67.75%.

@@            Coverage Diff             @@
##           master    #2219      +/-   ##
==========================================
- Coverage   75.52%   75.25%   -0.27%     
==========================================
  Files         452      454       +2     
  Lines       27479    27572      +93     
==========================================
- Hits        20753    20749       -4     
- Misses       6726     6823      +97     

Impacted Files	Coverage Δ
src/RelationTag.h	52.23% <0.00%> (-0.80%)	⬇️
src/ast/ExecutionOrder.h	100.00% <ø> (ø)
src/ast/Program.h	100.00% <ø> (ø)
src/ast/transform/ComponentInstantiation.cpp	92.36% <ø> (+0.38%)	⬆️
src/ast/transform/MinimiseProgram.h	100.00% <ø> (ø)
src/ast/transform/ResolveAliases.cpp	98.93% <ø> (ø)
src/ast/utility/SipsMetric.h	18.18% <ø> (ø)
src/ast/utility/Utils.h	100.00% <ø> (ø)
src/ast/utility/Visitor.h	57.33% <0.00%> (ø)
src/ast2ram/provenance/ClauseTranslator.h	100.00% <ø> (ø)
... and 133 more

[b-scholz]

Thanks for the contribution!