Disable active request of full mempools from our peers in bakers

Context

This MR disables an explicit call in the bakers to fetch complete mempools from our peers which produces a lot of network activity. In the context of the %(2023Q4) - Layer 1 - Reduce Block time milestone, our experiments showed that this activity was very impactful on the node which made it delay consensus operations injection, treatment and propagation when mempools gets large, like in our experiments.

Here are reports of experiments with and without the patch (on top of several other unrelated optimisations):

Report with bakers requesting operations:

Report with bakers not requesting operations:

Notice that the quorum takes 1s less to be reached with the patch and results are overall better.

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR