Snowflake delcare variable parsing fails

[TylerBrinks]

The following fails when parsing with the Snowflake dialect. Cross-referenced from the C# implementation.

    let sql = concat!(
    "DECLARE \
      query_id_1 VARCHAR; \
      query_id_2 VARCHAR; \
    BEGIN \
      SELECT TOP 100 LIVINGUNITID AS L1 \
                    ,PERSONID AS P1 \
      FROM ASSET_VIEWS.CV.CV_PII_ADV_CROSSWALK; \
      query_id_1 := SQLID; \
      RETURN [query_id_1]; \
    END;");

    snowflake().verified_stmt(sql);