Set the service name source to Instrumentation in entity when customer sets the service name OTEL resource attribute

[nathalapooja]

Description of the issue

Describe the problem or feature in addition to a link to the issues.

In the case of Appsignals with ADOT SDK, Operator sets the service name source to Instrumentation when the customer sets the service name. But for OTEL SDK, it doesn't have logic to add the service name source. Currently entity service name source is empty when the customer sets the service name OTEL attribute for OTLP metrics and logs.

Description of changes

How does this change address the problem?
Added logic to set the service name source to Instrumentation in entity when customer sets the service name OTEL resource attribute for OTLP metrics and logs.

License

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Tests

Describe what tests you have done.
Unit Tests
Manual Tests

Before Change

{"com.amazonaws.cloudwatch.entity.internal.deployment.environment":"eks: │
│ compass-ga2/default","com.amazonaws.cloudwatch.entity.internal.k8s.cluster.name":"compass-ga2","com.amazonaws.cloudwatch.entity.internal.k8s.namespace.name":"defaul │
│ t","com.amazonaws.cloudwatch.entity.internal.k8s.node.name":"ip-192-168-40-77.ec2.internal","com.amazonaws.cloudwatch.entity.internal.k8s.workload.name":"sample-app","com.amazonaws.cloudwatch.entity.internal.platform.type":"AWS::EKS","com.am │
│ azonaws.cloudwatch.entity.internal.service.name":"test-service","com.amazonaws.cloudwatch.entity.internal.type":"Service"}}                                                                                                                

After Change

  -> com.amazonaws.cloudwatch.entity.internal.type: Str(Service)\n     -> com.amazonaws.cloudwatch.entity.internal.service.name: Str(test-service)\n     -> com.ama │
│ zonaws.cloudwatch.entity.internal.deployment.environment: Str(eks:compass-ga2/default)\n     -> com.amazonaws.cloudwatch.entity.internal.platform.type: Str(AWS::EKS)\n     -> com.amazonaws.cloudwatch.entity.internal.k8s.cluster.name: Str(com │
│ pass-ga2)\n     -> com.amazonaws.cloudwatch.entity.internal.k8s.namespace.name: Str(default)\n     -> com.amazonaws.cloudwatch.entity.internal.k8s.workload.name: Str(sample-app)\n        -> 
com.amazonaws.cloudwatch.entity.internal.service.name.source: Str(Instrumentation)

Requirements

Before commit the code, please do the following steps.

1. Run make fmt and make fmt-sh
2. Run make lint

[musa-asad]

nit: mention that this resource attribute is always set when an application is instrumented by an otel sdk