Allow query tagging for Snowflake source

**Is your feature request related to a problem? Please describe.**
We use Cube to connect to Snowflake as a source, and need to track the performance of queries running inside of Snowflake. An issue we are running into is our BI tools that connect to cube to write query tags in the format of
```
/*
{...}
*/
```
but when rewriting in cube happens this is removed

**Describe the solution you'd like**
Ideally we would like to be able to pass those query tags from BI tools through cube into Snowflake so we can track performance, or have some way in cube to write query tags