[Behavior Flags] Track behavior flags in Snowplow

[mikealfare]

Housekeeping

• I am a maintainer of dbt-core

Short description

As a maintainer, I need to track what proportion of users are using legacy behavior, so that I know when it's safe to retire that behavior. We already fire a warning event when the flag evaluates to False. We need to track how often this occurs for each flag as a count of invocation id.

Acceptance criteria

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1. Any time a behavior flag evaluates to False, this gets tracked in our Snowplow instance
2. No events for behavior flags are tracked if the user has turned off anonymous tracking (this is existing behavior for all other tracking and should continue to be observed)

Suggested testing

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1. Create a scenario where the flag evaluates to False, verify that the callback is fired
2. Create a scenario where the flag evaluates to True, verify that the callback is not fired
3. Fire an event other than a BehaviorDeprecationEvent and verify that the callback is not fired

Impact to other teams

There's no immediate impact to any team. However, it would make sense for existing behavior flags in dbt-core to migrate to the new framework at some point.

Will backports be required?

No backports are required; this is new functionality.

[mikealfare]

Re-opening since we need the schema update as well.