Fix: use uint64_t for input and counter in countSetBits

[Rudra2637]

Description of Change

Updated the countSetBits function in bit_manipulation/count_of_set_bits.cpp to improve type safety and correctness:

• Changed the input parameter from int64_t to uint64_t to ensure only non-negative numbers are allowed.
• Changed the internal counter variable count from int to uint64_t to match the return type and prevent any theoretical overflow.
• Maintains original functionality for normal inputs.

This ensures the function is consistent, safe, and fully aligned with the intended use of counting set bits in non-negative integers.

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Checklist

• Added description of change
• Added file name matches File name guidelines
• Added tests and example, test must pass
• Added documentation so that the program is self-explanatory and educational - Doxygen guidelines
• Relevant documentation/comments is changed or added
• PR title follows semantic commit guidelines
• Search previous suggestions before making a new one, as yours may be a duplicate.
• I acknowledge that all my contributions will be made under the project's license.

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Notes:
Improves type safety for countSetBits function without changing its behavior for normal inputs.

[realstealthninja]

LGTM

[Rudra2637]

I am glad you liked it

[Rudra2637]

LGTM

Hey some of the files contain similar kind of problem should i fix them as well ?