Add `inputs_embeds` support for `.generate()` with BLOOM models
Author: akreal
Pull request: yes

# What does this PR do?

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Adds accepting `.generate()` calls with `inputs_embeds` on BLOOM models (following GPT2 example in #21405).

## Before submitting
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      Pull Request section?
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## Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
members/contributors who may be interested in your PR.

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 Please tag fewer than 3 people.

Models:

- text models: @ArthurZucker and @younesbelkada
- vision models: @amyeroberts and @NielsRogge
- speech models: @sanchit-gandhi
- graph models: @clefourrier

Library:

- flax: @sanchit-gandhi
- generate: @gante
- pipelines: @Narsil
- tensorflow: @gante and @Rocketknight1
- tokenizers: @ArthurZucker
- trainer: @sgugger

Integrations:

- deepspeed: HF Trainer: @stas00, Accelerate: @pacman100
- ray/raytune: @richardliaw, @amogkam

Documentation: @sgugger, @stevhliu and @MKhalusova

HF projects:

- accelerate: [different repo](https://github.com/huggingface/accelerate)
- datasets: [different repo](https://github.com/huggingface/datasets)
- diffusers: [different repo](https://github.com/huggingface/diffusers)
- rust tokenizers: [different repo](https://github.com/huggingface/tokenizers)

Maintained examples (not research project or legacy):

- Flax: @sanchit-gandhi
- PyTorch: @sgugger
- TensorFlow: @Rocketknight1

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@gante 

Comments:
_The documentation is not available anymore as the PR was closed or merged._

There seems to be a CircleCI issue when triggering the tests 🤔 

@akreal could you try following [these instructions](https://support.circleci.com/hc/en-us/articles/360056873811-Your-access-to-a-project-from-CircleCI-was-revoked-by-GitHub)? I'm not sure whether they will help, but they were the closest match I found based on CircleCI's error message.