Remove true from falsy values list in soy coercion docs.
Remove true from falsy values list in soy coercion docs.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=255912553

google/closure-templates,yext/closure-templates,yext/closure-templates,yext/closure-templates,yext/closure-templates,google/closure-templates,google/closure-templates,google/closure-templates,google/closure-templates