remove re-defination of FlaxWav2Vec2ForCTCModule
# What does this PR do?

Remove duplicate definations of `FlaxWav2Vec2ForCTCModule`
The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_15965). All of your documentation changes will be reflected on that endpoint.<|||||>The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_15965). All of your documentation changes will be reflected on that endpoint.