Write results of forces function object to preCICE

[uekerman]

Motivated from @ahmed-h-elsheikh s case:

Drag and lift on a geometry in OpenFOAM is computed via the forces function object (or more general OpenFOAM probes). It would be helpful to write this data to preCICE. Could be a dummy one-vertex helper mesh or, in the future, via global data precice/precice#1549.

Alternative: We could also avoid the forces function object and just directly compute the lift and drag in the adapter.

Yet another alternative: Do the integration in preCICE via an action. (Consider this if the realization in the adapter is too cumbersome).