Added "Snowflake" DBMS support (#5980)

* Added SQL queries for 'Snowflake' DBMS

* Added necessary constants for the 'Snowflake' DBMS

* Added the 'Snowflake' DBMS to existing conditional which adds dynamic values to hardcoded statements (queries.xml)

* Added plugin logic for the 'Snowflake' DBMS

* Modified 'dbs' query to include 'ORDER BY'

* Moved 'LIMIT' to appear before 'OFFSET'