[feature]: Google Tag Manager support (extensibility)

[ericerway]

Is your feature request related to a problem? Please describe.
Google Analytics is a key aspect of Magento 2 configuration and currently customization for Venia and our new PWA-based storefront. With this new extension, GTM will be supported as a standard option and included in Venia.

https://docs.magento.com/user-guide/marketing/google-universal-analytics.html

Describe the solution you'd like
Basic GTM capabilities across key shopping experiences in Venia including (but not limited to) the homepage, PLP, PDP and cart/checkout flow.

Describe alternatives you've considered
The solution should address GTM needs first but flexible to be used with other third-party tagging as well.

Additional context

Please let us know what packages this feature is in regards to:

• venia-concept
• venia-ui
• pwa-buildpack
• peregrine
• pwa-devdocs
• upward-js
• upward-spec
• create-pwa

[m2-assistant]

Hi @ericerway. Thank you for your report.
To help us process this issue please make sure that you provided sufficient information.

Please, add a comment to assign the issue: @magento I am working on this

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