server-tools/autovacuum_message_attachment/data/data.xml

<?xml version="1.0" encoding="utf-8"?>

<odoo noupdate="1">

        <record id="ir_cron_vacuum_message" model="ir.cron">
            <field name="name">AutoVacuum Mails and Messages</field>
            <field eval="False" name="active"/>
            <field name="user_id" ref="base.user_root"/>
            <field name="interval_number">1</field>
            <field name="interval_type">days</field>
            <field name="numbercall">-1</field>
            <field name="state">code</field>
            <field name="code">model.autovacuum('message')</field>
            <field eval="False" name="doall"/>
            <field name="model_id" ref="mail.model_mail_message"/>
        </record>

        <record id="ir_cron_vacuum_attachment" model="ir.cron">
            <field name="name">AutoVacuum Attachments</field>
            <field eval="False" name="active"/>
            <field name="user_id" ref="base.user_root"/>
            <field name="interval_number">1</field>
            <field name="interval_type">days</field>
            <field name="numbercall">-1</field>
            <field name="state">code</field>
            <field name="code">model.autovacuum('attachment')</field>
            <field eval="False" name="doall"/>
            <field name="model_id" ref="base.model_ir_attachment"/>
        </record>

</odoo>