Add Sudoku Solver using Backtracking algorithm - Implements depth-fir…

[harsha08-2k6]

• [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.
• [x] All new algorithms have a URL in their comments that points to Wikipedia or other similar explanations.
• [x] All new code is formatted with clang-format -i --style=file path/to/your/file.java.

[codecov-commenter]

Codecov Report

:x: Patch coverage is 58.82353% with 14 lines in your changes missing coverage. Please review. :white_check_mark: Project coverage is 78.48%. Comparing base (f693c44) to head (8e77bf4).

Files with missing lines	Patch %	Lines
...a/com/thealgorithms/backtracking/SudokuSolver.java	58.82%	14 Missing :warning:

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #7104      +/-   ##
============================================
- Coverage     78.50%   78.48%   -0.03%     
+ Complexity     6752     6748       -4     
============================================
  Files           759      759              
  Lines         22402    22404       +2     
  Branches       4400     4399       -1     
============================================
- Hits          17587    17583       -4     
- Misses         4109     4116       +7     
+ Partials        706      705       -1     

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[github-actions[bot]]

This pull request has been automatically closed because its workflows or checks failed and it has been inactive for more than 14 days. Please fix the workflows and reopen if you'd like to continue. Merging from main/master alone does not count as activity.