using "allOf" triggers exit with error "non supported '[]' type"

[winmillwill]

Describe the bug

When using allOf in the schema, the program exits with an error, even if there is only one schema in the list and that schema worked before.

To Reproduce

Steps to reproduce the behavior:

1. start with any working openapi v2 spec and terraform module
2. change the schema of anything from x to {allOf: [x]}
3. run terraform plan

Expected behaviour

Example:

Scenario:
Given a schema
When it uses allOf
Then the validator should detect that all of the schemas apply

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