Added Unit Tests for Shor’s Algorithm (#12318)

[adityakrmishra]

Summary

This PR adds unit tests for the classical implementation of Shor’s Algorithm.

Changes

• Created tests/cryptography/test_shor_algorithm.py
• Implemented test cases using pytest
• Verified correct factorization of composite numbers

Issue Reference

Closes #12318

Testing

Run the tests using:

pytest tests/cryptography/test_shor_algorithm.py

[algorithms-keeper]

Closing this pull request as invalid

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