[Bridges] Throw in Constraint.SlackBridge if scalar constant is nonzero (#2382)

Author: blegat

src/Bridges/Constraint/bridges/slack.jl

@@ -222,6 +222,7 @@ function bridge_constraint(
     f::MOI.AbstractScalarFunction,
     s::S,
 ) where {T,F,S}
+    MOI.throw_if_scalar_and_constant_not_zero(f, typeof(s))
     slack, slack_in_set = MOI.add_constrained_variable(model, s)
     new_f = MOI.Utilities.operate(-, T, f, slack)
     equality = MOI.add_constraint(model, new_f, MOI.EqualTo(zero(T)))

test/Bridges/lazy_bridge_optimizer.jl

@@ -323,11 +323,6 @@ function test_MOI_runtests_StandardSDPAModel()
             # sets of the same type are added.
             "test_model_LowerBoundAlreadySet",
             "test_model_UpperBoundAlreadySet",
-            # MOI.ScalarFunctionConstantNotZero is thrown, not of the original
-            # constraint, but of the bridged constraint. This seems okay. The
-            # fix would require that a bridge optimizer has a try-catch for this
-            # error.
-            "test_model_ScalarFunctionConstantNotZero",
         ],
     )
     return