using opentelemetry.io* namespace for extracing resource based on annotations from k8s Api #2330

[Horiodino]

change_type: sdk.go

• Modified the logic for iterating over pod annotations, utilizing pod.GetAnnotations() to identify and extract resources using the specified namespace prefix (constants.ReservedNamespace).

• Implemented the use of the OpenTelemetry.io namespace for extracting resource annotations from Kubernetes pods.

• Enhanced handling to streamline the extraction process and avoid overwriting existing resource mappings.

issues: [https://github.com//issues/2181]

#2330

TestCase ✅

?       github.com/open-telemetry/opentelemetry-operator/pkg/constants  [no test files]
ok      github.com/open-telemetry/opentelemetry-operator/pkg/collector/upgrade  
ok      github.com/open-telemetry/opentelemetry-operator/pkg/featuregate        
ok      github.com/open-telemetry/opentelemetry-operator/pkg/instrumentation    
ok      github.com/open-telemetry/opentelemetry-operator/pkg/instrumentation/upgrade    
ok      github.com/open-telemetry/opentelemetry-operator/pkg/sidecar    ```

[swiatekm]

The title of your PRs indicates it's adding support for attribute labels as well resource ones, but the code only seems to implement resources. Are you planning on a follow-up?

[Horiodino]

oh sorry for that , i have just added anotation for now because annotations are for attaching non-identifying metadata.
well @jaronoff97 should i add labels too ?

[jaronoff97]

I think we should only do from annotations and not labels. @Horiodino can you add a changelog and update the title to specify only annotations?

[Horiodino]

done

[swiatekm]

LGTM, small nitpick about naming. Please add a changelog entry as well, you can run make chlog-new to have the tooling generate a template for you.

[jaronoff97]

@Horiodino last thing to do here is add a changelog via make chlog-new. That will generate a new file in the .chloggen/ You can then edit that file with the necessary details at which point we can merge this :D

[Horiodino]

@jaronoff97 hearding about changelog first time ! i added it now

[pavolloffay]

Can we please document this in the root readme?

[jaronoff97]

@Horiodino when you get a chance, if you could add some documentation into the README.md then we should be able to merge this! 🙇

[swiatekm]

Suggested some phrasing changes to the documentation.