Support 7-zip compressed data files
COLLABORATOR
This should also resolve: https://github.com/huggingface/datasets/issues/3185.
2022-01-19T14:01:17Z
https://github.com/huggingface/datasets/issues/3541#issuecomment-1016493615
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2022-01-19T14:01:17Z
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**Is your feature request related to a problem? Please describe.**

We should support 7-zip compressed data files:
- [x] in `extract`:
  - #4672 
- [ ] in `iter_archive`: for streaming mode

both in streaming and non-streaming modes.
