Fix/remove safe loads path

[Elias0419]

This PR removes an unused code path in _generate_yaml()in sceptre/cli/helpers.py

yaml.safe_loads() does not exist, so that code path has never done anything.

sceptre/sceptre/cli/helpers.py

Line 157 in 69a8a5a

return yaml.safe_loads(stream)

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• [ ✓] Commit message starts with [Resolve #issue-number].
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• Added/Updated integration tests (if applicable).
• [ ✓] All unit tests (poetry run tox) are passing.
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[zaro0508]

yaml.safe_loads() does not exist

What do you mean it doesn't exist? The latest PyYAML docs seems to refers to its existence.

[Elias0419]

Hi @zaro0508 - Thanks for having a look

yaml.safe_load exists.

yaml.safe_loads (note the S) does not.

sceptre/sceptre/cli/helpers.py

Line 157 in 69a8a5a

return yaml.safe_loads(stream)