No, African dwarf frogs will not eat tetras. African dwarf frogs will only eat fish that are small enough to fit in their mouths, so unless you introduce the tetras when they’re very young, the tetras are unlikely to get eaten by the frogs. In fact, tetras and African dwarf frogs are considered excellent tankmates.
These tetra species make wonderful tankmates for African dwarf frogs:
With that said, in some cases, African dwarf frogs may nip on a tetra’s fins. This usually happens when the frogs are starving. If you keep your frogs well-fed, you’ll prevent them from hurting the tetras.