Allow torch==1.10.2, rename unit test file

[fhieber]

Previous pip install sockeye would uninstall torch==1.10.2 and install torch==1.10.0. We can safely depend on torch>=1.10.0 (1.10 and later).

Also rename a unit test module that was missed in the previous update.

Pull Request Checklist

• [x] Changes are complete (if posting work-in-progress code, prefix your pull request title with '[WIP]' until you can check this box.
• [x] Unit tests pass (pytest)
• [x] Were system tests modified? If so did you run these at least 5 times to account for the variation across runs?
• [x] System tests pass (pytest test/system)
• [x] Passed code style checking (./style-check.sh)
• [x] You have considered writing a test
• [x] Updated major/minor version in sockeye/__init__.py. Major version bump if this is a backwards incompatible change.
• [x] Updated CHANGELOG.md

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