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 91.30435% with 4 lines in your changes missing coverage. Please review.

Project coverage is 63.7%. Comparing base (fbbdb68) to head (4d45d2a).

❗ Current head 4d45d2a differs from pull request most recent head a507369

Please upload reports for the commit a507369 to get more accurate results.

Additional details and impacted files

@@           Coverage Diff           @@
##            main   #5422     +/-   ##
=======================================
+ Coverage   63.6%   63.7%   +0.1%     
=======================================
  Files        194     195      +1     
  Lines      12092   12126     +34     
=======================================
+ Hits        7699    7736     +37     
+ Misses      4174    4172      -2     
+ Partials     219     218      -1     

Files	Coverage Δ
detectors/azure/azurevm/vm.go	91.3% <91.3%> (ø)

... and 1 file with indirect coverage changes

[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.

[pyohannes]

I removed the mockable client object, and instead made the endpoint URL configurable.

Please have another look @dmathieu and @MrAlias.

[pyohannes]

@dmathieu @dashpole @MrAlias I hope I addressed all open comments, please have another look.