Replace assert-based validation with explicit errors in modular_division (#14204)

* Improve documentation for linear search algorithm

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Replace asserts with explicit validation in modular_division

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Update linear_search.py

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Co-authored-by: Anusha-DeviE <[email protected]>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Maxim Smolskiy <[email protected]>