Add saved queries for ongoing Snowflake threats

[egibs]

Background

Snowflake has released additional information on investigating and identifying malicious behavior to Snowflake accounts: https://community.snowflake.com/s/article/Communication-ID-0108977-Additional-Information

This PR adds saved queries to identify malicious behavior.

Changes

• Adds Snowflake queries applicable to the aforementioned KB article

Testing

• TBD