Implement SQL commenter as a Sequelize wrapper

[eliseier]

Motivation

Notion

The original google sqlcommenter Sequelize plugin included a lot of dependencies that we didn't need since we just wanted trace context (e.g. dependencies on opencensus, opentelemetry).

This forks the plugin and creates a minimal version.

Changes

1. Add makeMinimalStacktrace which gives us good context regarding a Sequelize query stacktrace.
2. Change wrapSequelize to auto-wrap the query.run method with a stacktrace comment

Note: We're essentially reaching in and changing private functions (query.run). TypeScript doesn't allow us to do this due to better enforced privacy, so it is required that we do so with a JS plugin instead of implementing the solution outright in our codebase with TS.

Testing

1. Added unit tests & ran with mocha
2. Logged the SQL queries to ensure it looks how we want it to.

[eliseier]

as a general note, i did find this article on warning against injecting dynamic information as comments for SQL queries since it ruins the cache:
https://www.adyen.com/knowledge-hub/injecting-metadata-as-comments

we might see some CPU usage go up since now, different origins of similar queries may result in separate cache entries; however, the stack information is generally deterministic

potential follow-ups:

• make this a configurable option that we can only turn on sometimes for debugging

[pxpeterxu]

This mostly looks good! Some small suggestions about where to put the escaping code, etc.

On your prepared statement note:

as a general note, i did find this article on warning against injecting dynamic information as comments for SQL queries since it ruins the cache: https://www.adyen.com/knowledge-hub/injecting-metadata-as-comments

we might see some CPU usage go up since now, different origins of similar queries may result in separate cache entries; however, the stack information is generally deterministic

potential follow-ups:

* make this a configurable option that we can only turn on sometimes for debugging

I took a look, and I think we don't need to worry about this quite yet -- https://www.adyen.com/knowledge-hub/injecting-metadata-as-comments seems to talk mostly about prepared statements using the PREPARE commands thanks to the Java library they use.

For Sequelize with MySQL, I don't believe Sequelize uses prepared statements; a quick search through the codebase seems to indicate that the only appearance of prepare is in the IBM DB2 driver, and MySQL likely just uses plain queries with substitutions, so we should be safe for now!