Fixes filter pruning use the statistics updated by the same filter (duckdb/duckdb#17425)

Fixes filter pruning use the statistics updated by the same filter (duckdb/duckdb#17425)

Fixes filter pruning use the statistics updated by the same filter (duckdb/duckdb#17425)

Fixes filter pruning use the statistics updated by the same filter (duckdb/duckdb#17425)

…18018)

fixes duckdblabs/duckdb-internal#5141

#17425 introduced an optimization
to replace `constant_or_null(true, X)` with an `is_not_null(X)` filter.
This was not tested well and assumes that `X` is just a
BOUND_COLUMN_REF. If `X` is a function (for example `coalesce(X,
'value')`) then this optimization does not produce the same results.

In the coalesce example, the column X may only contain `NULLS`, but
since it is coalesced with a constant value, the `IS NOT NULL` filter
will produce a different result.

I thought about adding an `IsNotNull()` filter on top of the
ExpressionFilter when propagating the statistics
(@propagate_get.cpp:104). This turns the optimization into a
`constant_or_null` into `Is not NULL (Coalesce('X', 'value'))`. The
problem there is that `constant_or_null` can have multiple children, so
it would turn into a conjunction and with all of the children.

There is definitely still room to optimize the `constant_or_null`
function, but since this is a bug fix, I tried to keep the diff small.