Dead Link for Available HF_Tasks

"The HF_TASK environment variable defines the task for the used 🤗 Transformers pipeline. A full list of tasks can be find [here](https://huggingface.co/transformers/main_classes/pipelines.html)."

The URL https://huggingface.co/transformers/main_classes/pipelines.html is a dead link and needs to be updated.

Search the documentation for the quoted HF_TASK text and inspect the referenced Hugging Face Transformers pipeline-task link. Replace the dead URL with the current full task-list URL, then verify that the updated link resolves and the surrounding wording remains accurate.

Written by the indexing model from the issue text.