SkyReelsV2DiffusionForcingPipeline does not check for available packages

[vladmandic]

Describe the bug

typically all pipelines check for available modules, for example:

if is_ftfy_available():
    import ftfy

however, recently added

• src/diffusers/pipelines/skyreels_v2/pipeline_skyreels_v2_diffusion_forcing.py
• src/diffusers/pipelines/skyreels_v2/pipeline_skyreels_v2_diffusion_forcing_i2v.py
• src/diffusers/pipelines/skyreels_v2/pipeline_skyreels_v2_diffusion_forcing_v2v.py

do not perform any checks and simply do:

import ftfy

which causes runtime error since ftfy is not a hard dependency for diffusers

Reproduction

see above

Logs

Failed to import diffusers.pipelines.skyreels_v2.pipeline_skyreels_v2_diffusion_forcing because of the following error (look up to see its traceback):
No module named 'ftfy'

System Info

diffusers==main

Who can help?

@yiyixuxu @sayakpaul @DN6 @asomoza