[StructApp] Remove inconsistency between static and transient adjoint formulations

[JonasHill]

📝 Description
Current situation:
Current implementation of adjoint formulations in structures and their primal counterparts have inconsistencies.
The residual formulation of static structural primals is:
$R = f - Ku$
The residual used in adjoint formulation is:
$R = Ku -f$
This inconsistency causes problems when we want to exend the same formulation for the transient adjoints, therefore this PR removes the inconsistency and makes the adjoint formulation to follow the residual formulation of the static primals.

The current implementation of the response function in structural mechanics provides the negative partial gradient ($-\frac{\partial J}{\partial u}$) to account for the inconsistency in the adjoint formulation.
This PR fixes the responses as well to follow the residual formulation of the primal counterparts.

🆕 Changelog

• Multiplying the AdjointFiniteDifferenceBaseElement::CalculateLeftHandSide matrix with minus 1
• Fixing the response functions