feat: add host.arch resource attribute

[rogercoll]

Changes

Adds the "host.arch" resource attribute to the Host detector.

Merge requirement checklist

• CONTRIBUTING guidelines followed
• Unit tests added/updated (if applicable)
• Appropriate CHANGELOG.md files updated for non-trivial, user-facing changes
• Changes in public API reviewed (if applicable)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 52.5%. Comparing base (56a6f45) to head (35b7860).

Additional details and impacted files

@@           Coverage Diff           @@
##            main     #59     +/-   ##
=======================================
+ Coverage   52.3%   52.5%   +0.2%     
=======================================
  Files         38      38             
  Lines       4967    4997     +30     
=======================================
+ Hits        2598    2628     +30     
  Misses      2369    2369             

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[lalitb]

I understand it is not related to this PR, but using a function pointer is bit unconventional for Rust. Closure or trait object could be more idiomatic. Something like (not tested):

pub struct HostResourceDetector {
    host_id_detect: Box<dyn HostIdDetector>,
}

trait HostIdDetector {
    fn detect(&self) -> Option<String>;
}
#[cfg(target_os = "linux")]
struct LinuxHostIdDetector;

#[cfg(target_os = "linux")]
impl HostIdDetector for LinuxHostIdDetector {
    fn detect(&self) -> Option<String> {
       Some("my_host_id")
   }
}
#[cfg(not(target_os = "linux"))]
struct NonLinuxHostIdDetector;

#[cfg(not(target_os = "linux"))]
impl HostIdDetector for NonLinuxHostIdDetector {
    fn detect(&self) -> Option<String> {
        None
    }
}

But not for this PR. Commented just that we know it can be improved :)

[rogercoll]

Thanks for the feedback, I will look into it 👀

[lalitb]

LGTM. Thanks for the PR :)