Fix: ensure dbutils.fs.ls lists directories with trailing '/'

[shindeakshay0211]

Fixes local directory listing to include folders as well as files. Directory paths now end with '/' and are correctly marked as directories.

[github-actions]

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Trigger:
go/deco-tests-run/sdk-py

Inputs:

• PR number: 1056
• Commit SHA: 1c19997d463636e6d98e14da265498ab0e5fe8d7

Checks will be approved automatically on success.

[shindeakshay0211]

fix: include directories in local file listing and update changelog