DAL: Add option to set batching of shards for verification

This is a follow-up to !18848 (merged)

What

Add the batching-time-interval option in the CLI to allow the user to set the time interval they want to accumulate shards before launching the cryptographic verification.

Why

To ease the configuration and testing of the feature.

How

By adding a command line option, a field in the configuration file and using this new data.

Manually testing the MR

One can now launch a dal node with --batching-time-interval disabled to have the sequential verification of shards, at reception time and --batching-time-interval 0.05 to set the batching to last 50ms. (Default value is 0.02 so 20ms).