Fides.gtm() should happen as part of the base fides.js script

[eastandwestwind]

Is your feature request related to a specific problem?

The problem is that Fides.gtm() is an additional call that is required as part of the onboarding process and can lead to both additional setup time and confusion for customers as they are setting up GTM itself.

Describe the solution you'd like

• Maintain backwards compatibility. We have current customers calling the Fides.gtm() method. We can replace it with a method that does nothing, with a warning that it's deprecated, but it still needs to exist and not error.
• Add a new config env var (default is true) enableGTM, and if it's true, we 1) add pushFidesVariableToGTM to our "FidesInitialized" and "FidesUpdated" event listeners and 2) ensure we're calling pushFidesVariableToGTM on Fides initialization (likely not needed if we just add to our event listeners).