Add sql parameter support to essql expression

[poffdeluxe]

Elasticsearch SQL supports passing parameters to queries.
We should add an argument to the essql expression function that allows users to pass in parameters to the query.

Some users are passing in parameters using the urlparam function and then passing that into the SQL function. This is particularly dangerous since there's no escaping in the SQL and SQL could be injected.

Additionally, at the moment, if you're using a Canvas variable to modify your SQL query, you have to use the string expression function to do a bunch of complicated string concatenation that is very hard to read. If we passed in parameters, it would make using variables in your SQL much easier.

[elasticmachine]

Pinging @elastic/kibana-presentation (Team:Presentation)