Added test cases for RodCuttingTest.java

[sunilnitdgp]

• [ ] I have read CONTRIBUTING.md.
• [ ] This pull request is all my own work -- I have not plagiarized it.
• [ ] All filenames are in PascalCase.
• [ ] All functions and variable names follow Java naming conventions.
• [ ] All new algorithms have a URL in their comments that points to Wikipedia or other similar explanations.
• [ ] All new code is formatted with clang-format -i --style=file path/to/your/file.java

[sunilnitdgp]

I request the maintainer(s) to merge my request using "hacktoberfest-accepted" label.

[siriak]

Linter is still failing

[sunilnitdgp]

@siriak Fixed the linter issue.

[sunilnitdgp]

@vil02 / @siriak Please review this and merge if everything looks good.

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This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions[bot]]

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