refactor: make update fn take &ExectionContext & put update fn together

[SteveLauC]

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• 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. Update 4 update functions' argument to &ExectutionContext

2. In main.rs, function run(), put all update functions together like this:

   #[cfg(windows)]
   { }
   #[cfg(target_os = "linux")]
   { }
   #[cfg(target_os = "macos")]
   { }
   #[cfg(target_os = "dragonfly")]
   { }
   #[cfg(target_os = "freebsd")]
   { }
   #[cfg(target_os = "openbsd")]
   { }
   #[cfg(target_os = "android")]
   { }
   #[cfg(unix)]
   { }
   #[cfg(not(any(
       target_os = "freebsd",
       target_os = "openbsd",
       target_os = "netbsd",
       target_os = "dragonfly"
   )))]
   { }

   so that contributors can easily find what is the appropriate place for their new update functions.

   One thing to note is that the order of these update functions being executed is changed and users may feel a little bit unfamiliar...

3. In main.rs, make install_tracing() private as it is only used in main.rs