Run Encoder Models using Transformers Backend

[R3hankhan123]

Check if without any code changes encoder models work with transformers backend or not. Should be trivial since encoder models does not use RoPe.

[R3hankhan123]

@Sanjeev900 is working on it. I cannot assign him so i assigned it to myself

[Sanjeev900]

Found some issues on torch-spyre, but these are non blocking issues.

#4316
#4317