Fix printing of Interval in LaTeX

[blegat]

Reproduce it with:

julia> model = Model();

julia> @variable(model, x);

julia> @constraint(model, x in MOI.Interval(0.5, 1.5))
x ∈ [0.5, 1.5]

julia> latex_formulation(model)
$$ \begin{aligned}
\text{feasibility}\\
Error showing value of type JuMP._LatexModel{Model}:
ERROR: MethodError: no method matching _escape_if_scientific(::typeof(mode), ::String)
The function `_escape_if_scientific` exists, but no method is defined for this combination of argument types.

Closest candidates are:
  _escape_if_scientific(::MIME{Symbol("text/latex")}, ::String)
   @ JuMP ~/.julia/dev/JuMP/src/print.jl:73
  _escape_if_scientific(::MIME, ::String)
   @ JuMP ~/.julia/dev/JuMP/src/print.jl:71

Stacktrace:
  [1] _string_round
    @ ~/.julia/dev/JuMP/src/print.jl:87 [inlined]
  [2] in_set_string(::MIME{Symbol("text/latex")}, set::MathOptInterface.Interval{Float64})
    @ JuMP ~/.julia/dev/JuMP/src/print.jl:1058

After the PR:

julia> latex_formulation(model)
$$ \begin{aligned}
\text{feasibility}\\
\text{Subject to} \quad & x \in [0.5, 1.5]\\
\end{aligned} $$

Found by @johnaoga in dionysos-dev/Dionysos.jl#383

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.55%. Comparing base (be7d350) to head (63237e7).
Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3866   +/-   ##
=======================================
  Coverage   97.55%   97.55%           
=======================================
  Files          44       44           
  Lines        6059     6059           
=======================================
  Hits         5911     5911           
  Misses        148      148           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.