[TRAX] Squashing the `LSHSelfAttention` and `SelfAttention` class hierarchy  - They don't inherit from `EfficientAttentionBase` anymore.
[TRAX] Squashing the `LSHSelfAttention` and `SelfAttention` class hierarchy
 - They don't inherit from `EfficientAttentionBase` anymore.

PiperOrigin-RevId: 345920267

google/trax,google/trax