unit tests and integration tests

[shalom938]

add integration tests to test the digma-agent.
see the smoke tests in otel extension, the digma agent testing can adopt the smoke tests that we have in otel extension and use the same otel testing utils to count traces.

see smoke tests examples here
https://github.com/digma-ai/otel-java-instrumentation/blob/9950442d7f770ecac10b406b08c979ec4bd95f06/agent-extension/src/test/java/com/digma/otel/javaagent/extension/smoketest