do not set updated_at when creating note

Description

When creating a new note for an issue via the API, one can specify created_at. However, I always see an "Edited ... ago" for the created note, which I think comes from always setting updated_at of the note to the current date when creating.

Proposal

Do not set updated_at when creating a note.

Links / references

#43712 (moved) suggests the same for the creation of issues.