Add try-with-resources to unclosed streams

Created by: artwo

This PR improves the handling of input and output streams by using the try-with-resources statement to ensure that they are closed. There is a correction on how the try-with-resources is used with multiple streams which is based in this documentation.

The PR is meant to fix the remaining sonarcloud issues of https://github.com/OpenAPITools/openapi-generator/issues/788.

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