Add Solovay-Strassen Primality test

[saahil-mahato]

Describe your change:

• Add an algorithm?
• Fix a bug or typo in an existing algorithm?
• Documentation change?

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[cclauss]

#6228 @tianyizheng02 @ChrisO345 Do we need more ways to test for prime numbers?

[tianyizheng02]

Do we need more ways to test for prime numbers?

@cclauss I think it's fine to add this. The Solovay–Strassen primality test is a specific, distinct algorithm for testing whether a number is (probably) prime, and it's an algorithm we don't have yet. I'd say having it for educational purposes is enough justification.

Fixed