EVM/Node: remove duplicated check

What

Removes a duplicated check

Why

Evm_state.apply_blueprint already has the responsibility to return a valid Apply_success, if the produced block is not the successor of the current head, it's definitely not a success.

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