Add race condition detection for uploading the PyManager index

[zooba]

No description provided.

[Copilot]

Pull Request Overview

This PR adds race condition detection when uploading the PyManager index to prevent conflicting publish steps.

• Modify _run and call_ssh to return command output.
• Introduce race condition checks based on index modification time and missing installs in the uploaded index file.
• Add a helper function to detect missing installations in the index.

Comments suppressed due to low confidence (1)

windows-release/merge-and-upload.py:236

• [nitpick] The variables 'x' and 'y' in the find_missing_from_index function are not descriptive. Consider renaming them to 'indexedKeys' and 'missingKeys' to better reflect their purpose.

x = {install_sortkey(i) for i in json.load(r)["versions"]}