Different signingConfig in multi-dimensional build flavors

Question

Small example will describe the case:

flavorDimensions 'shape', 'api'

productFlavors {
        fruit {
             dimension "shape"
        }

        vegtable {
             dimension "shape"
        }

        production {
             dimension "api"
        }

        development {
             dimension "api"
        }
}

Task: I need to keep different signing config for fruitProduction and fruitDevelopment flavors.

I have researched the gradle doc and I have not found the suitable task where I can override the config for special flavor.