gh-37174: fixed bug in `is_linearly_dependent()`, returns true for linearly dependent univariate polynomial.
`is_linearly_dependent()` returned wrong results for the univariate
polynomial ring because the `coefficients()` method of univariate
polynomials returns coefficients in the opposite order of `monomials()`:
```
sage: R.<q> = QQ[]
sage: p = q^4 + 3*q + 5
sage: p.monomials()
[q^4, q, 1]
sage: p.coefficients()
[5, 3, 1]
```
We fix this by making the `coefficient_matrix()` method to check for
univariate polynomial ring and make the order consistent.
Fixes: #37075
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URL: https://github.com/sagemath/sage/pull/37174
Reported by: Aman Moon
Reviewer(s): Travis Scrimshaw
