Update ga-requirements.md
Add link to smoke tests improving issue
P1 (e.g. cannot GA without these):
-* End-to-end tests
+* End-to-end tests ([#298](https://github.com/open-telemetry/opentelemetry-java-instrumentation/issues/298#issuecomment-664162169))
* OTLP, Jaeger and Zipkin
* Spring Boot and Wildfly
* (Wildfly chosen due to common javaagent issues around jboss modules and jboss logging)
