Copy note from System.Random supplementary documentation to main System.Random doc

[blowdart]

Describe the issue or suggestion

In the supplementary notes for System.Random it notes

To generate a cryptographically secure random number, such as one that's suitable for creating a random password, use one of the static methods in the System.Security.Cryptography.RandomNumberGenerator class.

This caveat should be mirrored in the API docs, below the initial paragraph

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[danmoseley]

@blowdart BTW, that conceptual doc you found still says " The implementation of the Random class is based on a modified version of Donald E. Knuth's subtractive random number generator algorithm. For more information, see D. E. Knuth. The Art of Computer Programming, Volume 2: Seminumerical Algorithms. Addison-Wesley, Reading, MA, third edition, 1997." .. in .NET Core, it's xoshiroNN (unless you supply a seed)

[blowdart]

@danmoseley yes and? That's correct, and it's not the point. The point is to highlight everywhere it shouldn't be used for anything that needs cryptographic strength.