baker: rename endorsement into attestation in errors and events

Context

This MR rename endorsement into attestation in the baker errors and events.

This MR only focus on the UX side (errors and event/messages) and do not rename endorsement in the encoding. This needed changes will be handled in a future MR.

Fixes #5389 (closed)

Manually testing the MR

CI green

and for the manual test:

dune exec tezt/manual_tests/main.exe -- --file baker_test.ml  -v 

Checklist

• n/a Document the interface of any function added or modified (see the coding guidelines)
• n/a Document any change to the user interface, including configuration parameters (see node configuration)
• n/a 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