GitLab

* type conversion

Default value of `control_guidance_start` and `control_guidance_end` in `StableDiffusionControlNetPipeline.check_inputs` causes `TypeError: object of type 'float' has no len()`

Proposed fix: 
Convert `control_guidance_start` and `control_guidance_end` to list if float

* Update src/diffusers/pipelines/controlnet/pipeline_controlnet.py

* Update src/diffusers/pipelines/controlnet/pipeline_controlnet.py
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

* Update src/diffusers/pipelines/controlnet/pipeline_controlnet.py
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

---------
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>