Co-erce non-present values like false to string

[bf4]

We have a resource which calls another resource, and specifically calls 'verify_filters'. We discovered that in 0.9 and 0.10 verify_filter calls raw.present? which is false when raw is false. This change makes the processing of the true and false consistent.

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Bug fixes and Changes to Core Features:

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Test Plan:

Reviewer Checklist:

• Maintains compliance with JSON:API
• Adequate test coverage exists to prevent regressions

[bf4]

@lgebhardt any objection to this? otherwise false is treated as not present