fix: use hasOwnProperty instead of `[]`
fix: use hasOwnProperty instead of `[]`

`keywordsBlockAndTransactionProperties[cur].some` is not a function error.

If current token (`cur`) is a method from Object like `toString`, `keywordsBlockAndTransactionProperties[cur]` is
keywordsBlockAndTransactionProperties['toString'] and would be a function, then `fn.some` would throw the error.

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