transformers

80996194 - [`feat`] Allow loading T5Gemma2Encoder with AutoModel (#43559)

[`feat`] Allow loading T5Gemma2Encoder with AutoModel (#43559) * Allow loading T5GemmaEncoder/T5GemmaDecoder This is valuable for Sentence Transformers, which may want to load the encoder only. I've added the decoder only to mirror the changes I need for the encoder. * Remove t5gemma2_decoder as I only have checkpoints for the encoder * Don't allow importing Decoder; exclusively focus on encoders