odoo16/addons/hr_contract/views/resource_calendar_views.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>
    <record id="resource_calendar_view_tree" model="ir.ui.view">
        <field name="name">resource.calendar.view.tree.inherit.hr.contract</field>
        <field name="model">resource.calendar</field>
        <field name="inherit_id" ref="resource.view_resource_calendar_tree"/>
        <field name="arch" type="xml">
            <field name="company_id" position="after">
                <field name="contracts_count"/>
            </field>
        </field>
    </record>

    <record id="resource_calendar_view_form" model="ir.ui.view">
        <field name="name">resource.calendar.view.form.inherit.hr.contract</field>
        <field name="model">resource.calendar</field>
        <field name="inherit_id" ref="resource.resource_calendar_form"/>
        <field name="arch" type="xml">
            <div name="button_box" position="inside">
                <button class="oe_stat_button" name="action_open_contracts"
                        type="object" icon="fa-book" groups="hr_contract.group_hr_contract_manager">
                    <field name="contracts_count" string="Contracts" widget="statinfo"/>
                </button>
            </div>
        </field>
    </record>
</odoo>