Added collatz sequence

[SaiSudhaV]

Describe your change:

Generates the collatz sequence and prints to the console.

• Add an algorithm?
• Fix a bug or typo in an existing algorithm?
• Documentation change?

References

Checklist:

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized.
• I know that pull requests will not be merged if they fail the automated tests.
• This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
• All new Java files are placed inside an existing directory.
• All filenames are in all uppercase characters with no spaces or dashes.
• All functions and variable names follow Java naming conventions.

[siriak]

The result is not very useful as a string, please return the sequence as some sort of enumerable or array

[github-actions]

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]

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