#27364 fixes a bug that _test_construction should have found -- except TestSuite is not called at all for any multivariate polynomial rings.

We add a bunch of TestSuite calls for the rings constructed as examples in polynomial_ring_constructor.

Many tests are failing; we skip these tests to make this ticket mergeable. In follow-up tickets, these failures should be fixed.

Related:

• https://groups.google.com/g/sage-devel/c/vGzNJKAQWbs/m/nhm1iIPWAwAJ
• https://groups.google.com/g/sage-devel/c/xiH9d4oBwaI/m/9Q0U1bUlAwAJ

CC: @tscrim @videlec @dkrenn @mwageringel @mezzarobba @yuan-zhou @novoselt @nbruin

Component: commutative algebra

Author: Matthias Koeppe

Branch/Commit: 73dfeb8

Reviewer: Vincent Delecroix, Travis Scrimshaw

Issue created by migration from https://trac.sagemath.org/ticket/31668