Update edge cases for dynamic error handling in VM

[austinabell]

Summary of changes
Changes introduced in this pull request:

• If there was a read or write that ran out of gas, the error would not be downcasted correctly, as it was just checking for encoding errors. To be safe, all downcasts are updated to use the one attached to ActorError where both EncodingError and ActorError can be downcasted from a dynamic error.
• Updates test runner to only skip invalid files now that all others are passing (and prints passes instead of failures)

Reference issue to close (if applicable)

Closes

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