Terms missing in `ExpBlock` and `LogBlock` Hessian evaluation

`ExpBlock.evaluate_hessian_component` and `LogBlock.evaluate_hessian_component` are missing the first order adjoint terms.

e.g.

```
continue_annotation()

a = AdjFloat(1.0)
b = exp(a)

rf = ReducedFunctional(b, Control(a))
rf.derivative()
print(f"{rf.hessian(1.0)=}")
```

displays `0.0`.