refactor(conway): use shared update_cost_model helper

Refactored the PlutusV2 cost model update test to use the shared
`conway_common.update_cost_model` helper instead of a local function.
This reduces code duplication and improves maintainability. Also updated
the test to use more descriptive temp_template names for clarity.

Author: mkoura

cardano_node_tests/tests/tests_conway/test_update_plutusv2_builtins.py

@@ -11,7 +11,6 @@
 from cardano_node_tests.tests import common
 from cardano_node_tests.tests.tests_conway import conway_common
 from cardano_node_tests.tests.tests_plutus_v2 import mint_raw
-from cardano_node_tests.utils import clusterlib_utils
 from cardano_node_tests.utils import configuration
 from cardano_node_tests.utils import governance_utils
 from cardano_node_tests.utils import helpers
@@ -95,85 +94,28 @@ def test_update_in_pv9(
         if len(init_cost_model) >= 185:
             pytest.skip("PlutusV2 cost model was already updated.")
 
-        cost_proposal_file = DATA_DIR / "cost_models_list_185_v2_v3.json"
-
-        def _update_cost_model() -> None:
-            anchor_data = governance_utils.get_default_anchor_data()
-            _name_template = f"{temp_template}_cost_model"
-
-            update_proposals = [
-                clusterlib_utils.UpdateProposal(
-                    arg="--cost-model-file",
-                    value=str(cost_proposal_file),
-                    name="",  # costModels
-                )
-            ]
-
-            cost_model_proposal = conway_common.propose_pparams_update(
-                cluster_obj=cluster,
-                name_template=_name_template,
-                anchor_url=anchor_data.url,
-                anchor_data_hash=anchor_data.hash,
-                pool_user=pool_user_lgp,
-                proposals=update_proposals,
-            )
-
-            # Make sure we have enough time to submit the votes in one epoch
-            clusterlib_utils.wait_for_epoch_interval(cluster_obj=cluster, start=1, stop=-40)
-            prop_epoch = cluster.g_query.get_epoch()
-
-            # Vote & approve the action
-            conway_common.cast_vote(
-                cluster_obj=cluster,
-                governance_data=governance_data,
-                name_template=f"{_name_template}_yes",
-                payment_addr=pool_user_lgp.payment,
-                action_txid=cost_model_proposal.action_txid,
-                action_ix=cost_model_proposal.action_ix,
-                approve_cc=True,
-            )
-
-            assert cluster.g_query.get_epoch() == prop_epoch, (
-                "Epoch changed and it would affect other checks"
-            )
-
-            # Wait for ratification
-            rat_epoch = cluster.wait_for_epoch(epoch_no=prop_epoch + 1, padding_seconds=5)
-            rat_gov_state = cluster.g_query.get_gov_state()
-            conway_common.save_gov_state(
-                gov_state=rat_gov_state, name_template=f"{_name_template}_{rat_epoch}"
-            )
-            rat_action = governance_utils.lookup_ratified_actions(
-                state=rat_gov_state,
-                action_txid=cost_model_proposal.action_txid,
-                action_ix=cost_model_proposal.action_ix,
-            )
-            assert rat_action, "Action not found in ratified actions"
-
-            # Wait for enactment
-            enact_epoch = cluster.wait_for_epoch(epoch_no=prop_epoch + 2, padding_seconds=5)
-            enact_gov_state = cluster.g_query.get_gov_state()
-            conway_common.save_gov_state(
-                gov_state=enact_gov_state, name_template=f"{temp_template}_enact_{enact_epoch}"
-            )
-            pparams = enact_gov_state.get("currentPParams") or {}
-            assert len(pparams["costModels"]["PlutusV2"]) == 185
-
         # Check that Plutus script fails as expected in PV9
         mint_raw.check_missing_builtin(
             cluster_obj=cluster,
-            temp_template=temp_template,
+            temp_template=f"{temp_template}_check1",
             payment_addr=payment_addrs_lgp[0],
             issuer_addr=payment_addrs_lgp[1],
         )
 
         # Update the PlutusV2 cost model
-        _update_cost_model()
+        updated_cost_models = conway_common.update_cost_model(
+            cluster_obj=cluster,
+            name_template=f"{temp_template}_cost_model",
+            governance_data=governance_data,
+            cost_proposal_file=DATA_DIR / "cost_models_list_185_v2_v3.json",
+            pool_user=pool_user_lgp,
+        )
+        assert len(updated_cost_models["PlutusV2"]) == 185
 
         # Check again that the Plutus script fails as expected in PV9
         mint_raw.check_missing_builtin(
             cluster_obj=cluster,
-            temp_template=temp_template,
+            temp_template=f"{temp_template}_check2",
             payment_addr=payment_addrs_lgp[0],
             issuer_addr=payment_addrs_lgp[1],
         )