refactor: rename update fn name & some cleanup

[SteveLauC]

Standards checklist:

• The PR title is descriptive.
• I have read CONTRIBUTING.md
• The code compiles (cargo build)
• The code passes rustfmt (cargo fmt)
• The code passes clippy (cargo clippy)
• The code passes tests (cargo test)
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What does this PR do

1. Rename two update functions to run_xxx()
2. Some cleanup in main.rs, put all update functions that belong to a specific OS together