🔒 Use cryptographically secure pseudo-random number generator

[google-labs-jules]

🎯 What: Fixed the vulnerability caused by using random.getrandbits to generate cryptographically weak pseudo-random numbers in BitVector/BitVector.py.
⚠️ Risk: Weak pseudo-random numbers generated via the random module are predictable. If the generated bit vectors are used in a cryptographic context, their predictability could result in compromise of keys, nonces, or other sensitive data, leading to a serious security vulnerability.
🛡️ Solution: Substituted random.getrandbits(width) with secrets.randbits(width) to provide cryptographically secure pseudo-random number generation as standard in modern Python libraries for sensitive operations.

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PR created automatically by Jules for task 16063814608875239824 started by @schwehr

[google-labs-jules]

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