Bengali Sans missing from Development Builds page

[DLasher106]

The Development Builds page for Bengali only has the serif fonts; Sans and Sans UI are missing.

[aelatham]

See #39. Sans UI is being phased out as part of the UI font removals. Only Sans is missing.

[simoncozens]

We haven't done a Bengali Sans release recently, but there's a team working on some improvements to it this year.