Query: SqlConstantExpression should have ctor which takes value and type

[smitpatel]

So that we don't need to construct ConstantExpression always to create new SqlConstant.

[ranma42]

@roji I believe you fixed this in #33210

See fbfd468#diff-31a49e080013a5417ff3104f9a840e3a5693f553c3ee840cdb7c8a4cb8e335f8

[roji]

Indeed, thanks for the pointer.