Support [NOT] MATERIALIZED keyword for WITH queries/CTEs

As mentioned in the esquelto docs (https://hackage.haskell.org/package/esqueleto-3.5.8.1/docs/Database-Esqueleto-Experimental-From-CommonTableExpression.html), postgres (>12) supports keywords which specifies that CTEs should be fully calculated/materialized. For us, this is a must for performance reasons.

It would be great if there was some way to do this in esquelto, so that we could use it everywhere instead of having to use `sqlQQ` in cases where we need to specify CTEs should be materialized.