Update JuMP syntax to use the new nonlinear interface (new)

[tmigot]

Supersed #321

Since, we test that problems are the "same" than JuMP, it imposed some reorganization on the ADNLPModels side.

• hs87 is blocking Issue with new JuMP operator for problem HS87 NLPModelsJuMP.jl#195
• we need to find the match in britgas (or a work around)

[codecov]

Codecov Report

Attention: Patch coverage is 65.97549% with 361 lines in your changes missing coverage. Please review.

Project coverage is 92.60%. Comparing base (65bda82) to head (f7ac619).
Report is 18 commits behind head on main.

Files with missing lines	Patch %	Lines
src/PureJuMP/britgas.jl	0.00%	361 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (65bda82) and HEAD (f7ac619). Click for more details.

HEAD has 2 uploads less than BASE

Flag	BASE (65bda82)	HEAD (f7ac619)
	3	1

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #339      +/-   ##
==========================================
- Coverage   99.82%   92.60%   -7.22%     
==========================================
  Files        1078     1078              
  Lines       12184    12042     -142     
==========================================
- Hits        12163    11152    -1011     
- Misses         21      890     +869     

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