Get fractional demand for the representative t in node_injection constr.

Otherwise we get infeasibilities, because we will be asking
the injections over one representative period to be equal to the
fractional demand of all the represented ones. That doesn't make any
sense.

src/constraints/constraint_node_injection.jl

@@ -30,7 +30,8 @@ function add_constraint_node_injection!(m::Model)
         (node=n, stochastic_path=s, t_before=t_before, t_after=t_after) => @constraint(
             m,
             + expr_sum(
-                + node_injection[n, s, t] + demand[
+                + node_injection[n, s, t]
+                + demand[
                     (node=n, stochastic_scenario=s, analysis_time=t0, t=representative_time_slice(m, t))
                 ]
                 # node slack
@@ -41,8 +42,8 @@ function add_constraint_node_injection!(m::Model)
                 init=0,
             )
             + expr_sum(
-                fractional_demand[(node=n, stochastic_scenario=s, analysis_time=t0, t=t)]
-                * demand[(node=ng, stochastic_scenario=s, analysis_time=t0, t=t)]
+                fractional_demand[(node=n, stochastic_scenario=s, analysis_time=t0, t=representative_time_slice(m, t))]
+                * demand[(node=ng, stochastic_scenario=s, analysis_time=t0, t=representative_time_slice(m, t))]
                 for (n, s, t) in node_injection_indices(
                     m; node=n, stochastic_scenario=s, t=t_after, temporal_block=anything
                 )