Increase fontSize of PieChart

[JonDum]

https://github.com/mantinedev/mantine/blob/7598a26c6c057f914799ee3a63de4fc5417a09b9/packages/@mantine/charts/src/PieChart/PieChart.tsx#L180-190

Looks like it's hard coded to 12. Maybe we can pass props down to the label so it can be user controlled?