encoding: remove last occurences of legacy_attestation_name usage in octez codebase

What

The time to put the legacy attestation name endorsement to sleep has come. This MR is part of a set of MRs that target to remove the support for this old name.

This MR removes last occurrences of deprecated operations encoding using legacy attestation name in Octez code.

Why

How

Use encodings without legacy attestation name instead of the one with legacy attestation name. Binary encodings are the same.

Manually testing the MR

CI green

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