mitra - notification types

[technicat]

update mitra platform support of notification types

https://codeberg.org/silverpill/mitra/src/branch/main/docs/openapi.yaml

Notification:
      type: object
      properties:
        id:
          description: The id of the notification in the database.
          type: string
        type:
          description: The type of event that resulted in the notification.
          type: string
          enum:
            - follow
            - follow_request
            - reply
            - favourite
            - emoji_reaction
            - mention
            - reblog
            - subscription
            - subscription_expiration
            - move
            - admin.sign_up
          example: reply
        created_at:
          description: The timestamp of the notification.
          type: string
          format: date-time
        account:
          $ref: '#/components/schemas/Account'
        status:
          $ref: '#/components/schemas/Account'