Add a resource detector for Azure VMs

[pyohannes]

Fixes #5421

This PR adds a resource detector for Azure VMs which sets values according to to semantic conventions for host, cloud, and os resources:

• cloud.provider
• cloud.platform
• host.id
• host.name
• host.type
• os.type
• os.version

[codecov]

Codecov Report

Attention: Patch coverage is 78.18182% with 12 lines in your changes are missing coverage. Please review.

Project coverage is 63.4%. Comparing base (1c0eae0) to head (1967dbb).

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #5422   +/-   ##
=====================================
  Coverage   63.3%   63.4%           
=====================================
  Files        194     195    +1     
  Lines      12042   12097   +55     
=====================================
+ Hits        7633    7676   +43     
- Misses      4192    4204   +12     
  Partials     217     217           

Files	Coverage Δ
detectors/azure/vm/vm.go	78.1% <78.1%> (ø)

[MrAlias]

@pyohannes we will want to add you as an owner for this.

[MrAlias]

@pyohannes we will want to add you as an owner for this.

@pyohannes please go ahead and add this module here with yourself and the go-approvers as the code owners.

[pyohannes]

@pyohannes please go ahead and add this module here with yourself and the go-approvers as the code owners.

@MrAlias Done, I added myself as a code owner.

[dmathieu]

Since this method is mocked in the Detect test, could we test it anyway? (if we move the IP/port for the metadata endpoint into private variables, we can change them to an httptest endpoint in tests).

[pyohannes]

Yes, if so desired we can do that. We don't need to mock the method then, but just make the endpoint configurable.