[ADD] string-method-name: Add string-method-name check to preserve inheritability

Bad

    name = fields.Char(
        compute=_compute_name,
        search=_search_name,
        inverse=_inverse_name,
    )

Good

    name = fields.Char(
        compute="_compute_name",
        search="_search_name",
        inverse="_inverse_name",
    )

Fix OCA/odoo-pre-commit-hooks#126

Author: moylop260