Minor: require pyyaml > 3.13 to avoid an error.

[concretevitamin]

<= 3.13 may encounter ultralytics/yolov5#414.

Tested pip install -e:

Collecting pyyaml<=5.3.1,>3.13
  Downloading PyYAML-5.3.1.tar.gz (269 kB)
     ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 269.4/269.4 kB 4.2 MB/s eta 0:00:00
  Preparing metadata (setup.py) ... done

Note however at the end

kubernetes 26.1.0 requires pyyaml>=5.4.1, but you have pyyaml 5.3.1 which is incompatible.
Successfully installed pyyaml-5.3.1 skypilot-1.0.0.dev0

which means our k8s support seems to conflict with the explicit <= 5.3.1 pin. @romilbhardwaj

Tested (run the relevant ones):

• Code formatting: bash format.sh
• Any manual or new tests for this PR (please specify below)
• All smoke tests: pytest tests/test_smoke.py
• Relevant individual smoke tests: pytest tests/test_smoke.py::test_fill_in_the_name
• Backward compatibility tests: bash tests/backward_comaptibility_tests.sh

[romilbhardwaj]

Thanks @concretevitamin!

Tried fresh install on an empty container. Ran pip install -e .[all] and didn't run into the k8s dependency issue - it simply installed an older version. Logs.

That said, the dependency issue may occur for folks who already have newer version of kubernetes installed. As suggested in review comment, can you also try pyyaml >=6.0.1?

[romilbhardwaj]

With yaml/pyyaml#702 merged and PyYAML 6.0.1, awscli 1.29.4 released, we might also be able to allow >=6.0.1 here. Should we test with that too?

[concretevitamin]

Generally, people may not constantly upgrade their tools (aws-cli for example) to get those fixes. I think supporting latest versions can be deferred.

[romilbhardwaj]

as we discussed on call, lets defer >=6.0.1 for this PR but let's file an issue and get to it soon