Saving Parameter Values takes too long

After changing the parametrization of a (native) skill, it takes quite some time for fluxio to save the new parametrization.

This is because we update the values on a per-parameter basis and thus the time it takes depends on the number of parameters the skill has. (Also, waiting for each call to return before firing the next one is just slow)

To fix this, we need an endpoint that takes all parameters of the skill and does the update in bulk. This will greatly reduce the amount of network calls and the time it takes to complete the action in the frontend (ui feels more responsive).