Remove support for Fastly WAF (legacy EoL product)

[kpfleming]

Support for the Fastly WAF (legacy, not Next-Gen WAF) product has been removed. The product passed its End-of-Life date quite some time ago, and it is no longer in use by customers.

All Submissions:

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

New Feature Submissions:

• Does your submission pass tests?

Changes to Core Features:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your core changes, as applicable?
• Have you successfully run tests with your changes locally?

User Impact

• What is the user impact of this change? - Fastly WAF support has been removed.

Are there any considerations that need to be addressed for release?

This is a breaking change.

[philippschulte]

LGTM. Thank you!

[kpfleming]

Reverting to draft because the placement attributes cannot be removed.