Feature 3: Add-on of KMeansClustering Algorithm in backtracking folder

[Jivan052]

• [X] I have read CONTRIBUTING.md.
• [X] This pull request is all my own work -- I have not plagiarized it.
• [X] All filenames are in PascalCase.
• [X] 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

[Jivan052]

@yanglbme any changes required?

[siriak]

Please fix PR checks