fix: Prevent AJV logs from contaminating output

[nellh]

Some datasets on OpenNeuro are having JSON output contaminated by this output from AJV's internal logging:

strict mode: missing type "array" for keyword "maxItems" at "#/properties/ScreenResolution/anyOf/0/items" (strictTypes)
strict mode: missing type "array" for keyword "minItems" at "#/properties/ScreenResolution/anyOf/0/items" (strictTypes)
strict mode: missing type "array" for keyword "maxItems" at "#/properties/ScreenSize/anyOf/0/items" (strictTypes)
strict mode: missing type "array" for keyword "minItems" at "#/properties/ScreenSize/anyOf/0/items" (strictTypes)

Examples include ds005810 and ds005811.

[effigies]

Looks like we need a schema fix as well?