Update the signature of the `calculate_excess_blob_gas` function

The way the `calculate_excess_blob_gas` function is configured, it requires the parent header as an input. It cannot be used as is in the `t8n` tool since complete headers cannot be constructed in t8n. This means we have to re-implement the logic again in t8n.

We need to move towards a solution where we can simply just call the `calculate_excess_blob_gas` function within the `t8n` tool