EVM Node: Store gc parameters in the store

In this patch, we force users to explicitely set the desired retention period when they use the rolling mode, and we store this information in the store. This forces users to decide how much history they will keep, which will reduce the risk for us to introduce breaking changes by modifying the default configuration.

This patch also remove the ability to switch from rolling to archive. This could be introduced later, but at first, it is probably less confusing to force a user to reimport an archive node instead.

Manually testing the MR

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