Updating error message on ambiguous variable

[yashvardhan747]

As keyword argument "category" no longer exist. Error message on ambiguous variable needs to be updated

Closes #2035

[codecov]

Codecov Report

Merging #2222 into master will increase coverage by 0.88%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #2222      +/-   ##
==========================================
+ Coverage   91.12%   92.00%   +0.88%     
==========================================
  Files          42       42              
  Lines        4122     4864     +742     
==========================================
+ Hits         3756     4475     +719     
- Misses        366      389      +23     

Impacted Files	Coverage Δ
src/macros.jl	93.75% <100.00%> (+1.12%)	⬆️
src/operators.jl	88.35% <0.00%> (-0.61%)	⬇️
src/callbacks.jl	100.00% <0.00%> (ø)
src/variables.jl	96.17% <0.00%> (+0.29%)	⬆️
src/Containers/SparseAxisArray.jl	81.73% <0.00%> (+1.21%)	⬆️
src/JuMP.jl	75.00% <0.00%> (+1.38%)	⬆️
src/constraints.jl	93.81% <0.00%> (+1.96%)	⬆️
src/nlp.jl	94.51% <0.00%> (+2.24%)	⬆️
src/objective.jl	94.00% <0.00%> (+2.82%)	⬆️
... and 3 more

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[odow]

Tests? Coverage is a little confused.

[yashvardhan747]

Yeah cool, I add tests.
But the errors are LoadError, Can you tell how to test LoadError?

[yashvardhan747]

Fine, I used @test_macro_throws :)

[odow]

Just waiting for the CI to pass. I had to give it a kick to restart a couple of times. Some sort of connection issue.