server-tools/base_cron_oneshot/data/ir_cron.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>
  <data noupdate="1">
    <record id="cron_oneshot_cleanup" model="ir.cron" forcecreate="True">
      <field name="name">Oneshot cron cleanup</field>
      <field name="user_id" ref="base.user_root"/>
      <field name="model_id" ref="model_ir_cron"/>
      <field name="state">code</field>
      <field name="code">model.cron_oneshot_cleanup()</field>
      <field name="interval_number">1</field>
      <field name="interval_type">days</field>
      <!-- make it run the day after installation at midnight -->
      <field name="nextcall" eval="(DateTime.now() + timedelta(days=1)).strftime('%Y-%m-%d 00:00:00')" />
      <field name="numbercall">-1</field>
      <field name="doall" eval="False"/>
    </record>
  </data>
</odoo>