Use OTLP/Protobuf Exporter for AMW Endpoint

[JacksonWeber]

This pull request updates how OTLP metric exporters are handled in the AKSLoader agent, switching from the HTTP-based OTLP metrics exporter to the protobuf-based version. It also adds a new unit test to verify that the correct exporter is created when the environment variable for protocol is set to http/protobuf. Additionally, the dependencies in package.json are updated to reflect this change.

Dependency and exporter updates:

• Replaced the @opentelemetry/exporter-metrics-otlp-http dependency with @opentelemetry/exporter-metrics-otlp-proto in package.json, ensuring that the project uses the protobuf-based exporter for OTLP metrics.
• Updated the import and instantiation in aksLoader.ts to use OTLPMetricExporter from the protobuf package instead of the HTTP package, aligning the code with the new dependency. [1] [2]

Testing improvements:

• Added a unit test in aksLoader.tests.ts to verify that when the OTEL_EXPORTER_OTLP_METRICS_PROTOCOL environment variable is set to http/protobuf, the AKSLoader correctly creates an OTLP protobuf metrics exporter.