⚗️ Create a Market_data_client to support finnhub/alphavantage/Twelvedata

[mraniki]

    if settings.finnhub_api_key:
        self.data_client = finnhub.Client(
            api_key=settings.finnhub_api_key)
    if settings.alphavantage_api_key:
        self.data_client = AlphavantageClient().with_api_key(
            settings.alphavantage_api_key)
    if settings.twelvedata_api_key:
        self.data_client = TDClient(apikey=settings.twelvedata_api_key)