[Journal] Remover Campos unpublish_reason e is_public

[cesarbruschetta]

Remover o campo unpublish_reason, esse campo é so utilizado para saber se o periodico deve ser mostrado no site. Ele so foi implementado devido ao lote de campo do ticker #8

remover trecho do codigo abaixo e seus testes tambem

https://github.com/scieloorg/document-store/blob/master/documentstore/domain.py#L619

    @property
    def unpublish_reason(self):
        return BundleManifest.get_metadata(self._manifest, "unpublish_reason")

    @unpublish_reason.setter
    def unpublish_reason(self, value: str):
        _value = str(value)
        self.manifest = BundleManifest.set_metadata(
            self._manifest, "unpublish_reason", _value
        )

    @property
    def is_public(self):
        return BundleManifest.get_metadata(self._manifest, "is_public", True)

    @is_public.setter
    def is_public(self, value: bool):
        self.manifest = BundleManifest.set_metadata(self._manifest, "is_public", value)

https://github.com/scieloorg/document-store/blob/master/tests/test_domain.py#L835

 def test_unpublish_reason_is_empty_str(self):
        journal = domain.Journal(id="0034-8910-rsp-48-2")
        self.assertEqual(journal.unpublish_reason, "")

    def test_set_unpublish_reason(self):
        journal = domain.Journal(id="0034-8910-rsp-48-2")
        journal.unpublish_reason = "not-open-access"
        self.assertEqual(journal.unpublish_reason, "not-open-access")
        self.assertEqual(
            journal.manifest["metadata"]["unpublish_reason"],
            [("2018-08-05T22:33:49.795151Z", "not-open-access")],
        )

    def test_is_public_is_default_true(self):
        journal = domain.Journal(id="0034-8910-rsp-48-2")
        self.assertTrue(journal.is_public)

    def test_set_is_public(self):
        journal = domain.Journal(id="0034-8910-rsp-48-2")
        journal.is_public = True
        self.assertTrue(journal.is_public)
        self.assertEqual(
            journal.manifest["metadata"]["is_public"],
            [("2018-08-05T22:33:49.795151Z", True)],
        )

    def test_set_is_public_to_false(self):
        journal = domain.Journal(id="0034-8910-rsp-48-2")
        journal.is_public = False
        self.assertFalse(journal.is_public)
        self.assertEqual(
            journal.manifest["metadata"]["is_public"],
            [("2018-08-05T22:33:49.795151Z", False)],
        )