Fix block placement filter format not found error

Fun note: I stumbled upon how this bug was introduced. Turns out that in #2789097 🐛 No Block Output Fixed , Rajab Natshah → submitted patch #11 🐛 No Block Output Fixed , and promptly submitted a patch the required use statement. But, when it was finally committed over a year and a half later, the commit was missing the changes from patch #12 🐛 No Block Output Fixed . Hopefully this gets adopted sooner.

am finding in TocFilterBlock ln 34 $format_id is null, we need to verify this.

Patch #4 works for me. Thanks.