integration tests for additional international holidays (#529)

Author: bhausleitner

tests/test_integration.py

@@ -372,6 +372,10 @@ def test_events():
     # add the country specific holidays
     m = m.add_country_holidays("US", mode="additive", regularization=0.5)
     m.add_country_holidays("Indonesia")
+    m.add_country_holidays("Thailand")
+    m.add_country_holidays("Philippines")
+    m.add_country_holidays("Pakistan")
+    m.add_country_holidays("Belarus")
     history_df = m.create_df_with_events(df, events_df)
     metrics_df = m.fit(history_df, freq="D")
     future = m.make_future_dataframe(df=history_df, events_df=events_df, periods=30, n_historic_predictions=90)