fix(#1966): go2Gno loses type info

[omarsy]

fixes #1966

Contributors' checklist...

• [ ] Added new tests, or not needed, or not feasible
• [ ] Provided an example (e.g. screenshot) to aid review or the PR is self-explanatory
• [ ] Updated the official documentation or not needed
• [ ] No breaking changes were made, or a BREAKING CHANGE: xxx message was included in the description
• [ ] Added references to related issues and PRs
• [ ] Provided any useful hints for running manual tests
• [ ] Added new benchmarks to generated graphs, if any. More info here.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 85.71429% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 48.85%. Comparing base (ccc6d5b) to head (3c7b5ed).

Files	Patch %	Lines
gnovm/pkg/gnolang/preprocess.go	85.71%	1 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2016      +/-   ##
==========================================
- Coverage   49.04%   48.85%   -0.20%     
==========================================
  Files         576      579       +3     
  Lines       77556    78038     +482     
==========================================
+ Hits        38035    38122      +87     
- Misses      36439    36830     +391     
- Partials     3082     3086       +4     

Flag	Coverage Δ
gnovm	42.14% <85.71%> (+0.12%)	:arrow_up:

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[thehowl]

cc @ltzmaxwell

[ltzmaxwell]

thank you for your work, start looking.

[ltzmaxwell]

cc @deelawn for a second look.