Ojs\JournalBundle\Entity\Section:
    type: entity
    repositoryClass: Ojs\JournalBundle\Entity\SectionRepository
    table: section
    cache:
        usage: NONSTRICT_READ_WRITE
    manyToOne:
       journal:
          targetEntity: Journal
          joinColumn:
            name: journal_id
            referencedColumnName: id
          inversedBy: sections
    oneToMany:
        articles:
            targetEntity: Article
            mappedBy: section
            cascade: ["persist", "merge"]
            fetch: EXTRA_LAZY
    id:
        id:
            type: integer
            id: true
            generator:
                strategy: AUTO
    fields:
        allowIndex:
            type: boolean
            column: allow_index
            nullable: true
            options:
                default: true
            gedmo:
                - versioned
        hideTitle:
            type: boolean
            column: hide_title
            nullable: true
            options:
                default: false
        sectionOrder:
            type: integer
            column: section_order
            nullable: false
            options:
                default: 1
        createdBy:
           type: string
           gedmo:
             blameable:
               on: create
        updatedBy:
           type: string
           gedmo:
             blameable:
               on: update
    lifecycleCallbacks: {  }
    gedmo:
        loggable: true

Ojs\JournalBundle\Entity\Section:
    type: entity
    repositoryClass: Ojs\JournalBundle\Entity\SectionRepository
    table: section
    cache:
        usage: NONSTRICT_READ_WRITE
    manyToOne:
       journal:
          targetEntity: Journal
          joinColumn:
            name: journal_id
            referencedColumnName: id
          inversedBy: sections
    oneToMany:
        articles:
            targetEntity: Article
            mappedBy: section
            cascade: ["persist", "merge"]
            fetch: EXTRA_LAZY
    id:
        id:
            type: integer
            id: true
            generator:
                strategy: AUTO
    fields:
        allowIndex:
            type: boolean
            column: allow_index
            nullable: true
            options:
                default: true
            gedmo:
                - versioned
        hideTitle:
            type: boolean
            column: hide_title
            nullable: true
            options:
                default: false
        sectionOrder:
            type: integer
            column: section_order
            nullable: false
            options:
                default: 1
        createdBy:
           type: string
           gedmo:
             blameable:
               on: create
        updatedBy:
           type: string
           gedmo:
             blameable:
               on: update
           nullable: true
    lifecycleCallbacks: {  }
    gedmo:
        loggable: true

Make updatedBy field of Section nullable
Make updatedBy field of Section nullable
