Update Utils.java

[cragkhit]

Hi. We are researchers from Mahidol University, Thailand, and the State University of Ceará, Brazil, working on a research project for improving open-source projects by using the latest accepted answer from Stack Overflow that matched your code snippet. We found this recommendation for improving your code from https://stackoverflow.com/questions/9292954/how-to-make-a-copy-of-a-file-in-android/9293885#9293885.

Note: Our study is approved by the Institutional Review Board of Mahidol University. You can find the participant information sheet explaining this study https://drive.google.com/file/d/1ml5AqrtWQ9pnifTQyTFTcWQmwp6RuPA7/view?usp=sharing.

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Proposed change

Added try-finally to properly close the input and output streams.