Read the execution count from the Python kernel

### Problem

https://github.com/jupyterlite/jupyterlite/pull/492 added a check to not increment the execution count if `store_history` is set to `false`.

This check happens in the base kernel class here:

https://github.com/jupyterlite/jupyterlite/blob/cb66d86e9b10cedc41f6bad77e3a25a97efb9c44/packages/kernel/src/kernel.ts#L536-L538

This means the JS, Python and potentially other kernels get that behavior automatically if they inherit from `BaseKernel`.

### Proposed Solution

We should check whether we would like to read the `execution_count` from the specialized kernels if available.

In the case of Pyolite that might mean reading it from here:

https://github.com/jupyterlite/jupyterlite/blob/72ebada70067afcd88ddcd283f4b7f0baf36cbdb/packages/pyolite-kernel/src/worker.ts#L181-L185

### Additional context

Raised in https://github.com/jupyterlite/jupyterlite/pull/492