add new benchmark for sparse AD on simple loop written diffusion operator

Author: yolhan83

benchmarks/AutomaticDifferentiationSparse/ManualLoopDissusionSparseAD.jmd

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+---
+title: Diffusion operator loop sparse AD benchmarks 
+author: Yolhan Mannes
+---
+
+```julia
+using DifferentiationInterface
+using DifferentiationInterfaceTest
+using LinearAlgebra
+using SparseConnectivityTracer: TracerSparsityDetector
+using SparseMatrixColorings
+import Enzyme,ForwardDiff,Mooncake
+```
+
+## Backends tested
+
+```julia
+bcks = [
+    AutoEnzyme(mode=Enzyme.Reverse),
+    AutoEnzyme(mode=Enzyme.Forward),
+    AutoMooncake(config=nothing),
+    AutoForwardDiff(),
+    AutoSparse(
+        AutoForwardDiff();
+        sparsity_detector=TracerSparsityDetector(),
+        coloring_algorithm=GreedyColoringAlgorithm()
+    ),
+    AutoSparse(
+        AutoEnzyme(mode=Enzyme.Forward);
+        sparsity_detector=TracerSparsityDetector(),
+        coloring_algorithm=GreedyColoringAlgorithm()
+    )
+    ]
+```
+
+## Diffusion operator simple loop
+
+```julia
+uin() = 0.0
+uout() = 0.0
+function Diffusion(u)
+    du = zero(u)
+    for i in eachindex(du,u)
+        if i == 1
+            ug = uin()
+            ud = u[i+1]
+        elseif i == length(u)
+            ug = u[i-1]
+            ud = uout()
+        else
+            ug = u[i-1]
+            ud = u[i+1] 
+        end
+        du[i] = ug + ud -2*u[i]
+    end
+    return du
+end;
+```
+
+## Manual jacobian
+```julia
+function DDiffusion(u)
+    A = diagm(
+        -1 => ones(length(u)-1),
+        0=>-2 .*ones(length(u)),
+        1 => ones(length(u)-1))
+    return A
+end;
+```
+
+## Define Scenarios
+
+```julia
+u = rand(1000)
+scenarios = [ Scenario{:jacobian,:out}(Diffusion,u,res1=DDiffusion(u))];
+```
+
+## Run Benchmarks
+
+```julia
+df = benchmark_differentiation(bcks, scenarios)
+```