Apply SQL compilation to sqltext for column-level CHECK constraint

Apply SQL compilation to sqltext for column-level CHECK constraint

Fixed bug where a column-level :class:`.CheckConstraint` would fail
to compile the SQL expression using the underlying dialect compiler
as well as apply proper flags to generate literal values as
inline, in the case that the sqltext is a Core expression and
not just a plain string.   This was long-ago fixed for table-level
check constraints in 0.9 as part of :ticket:`2742`, which more commonly
feature Core SQL expressions as opposed to plain string expressions.

Change-Id: I1301ba4b40063e91bc47726aecc5f4990ffcaeda
Fixes: #3957