Make HttpStatusConverter package private (#5268)

Author: Mateusz Rzeszutek

instrumentation-api/src/main/java/io/opentelemetry/instrumentation/api/instrumenter/http/HttpClientStatusConverter.java

@@ -7,10 +7,28 @@
 
 import io.opentelemetry.api.trace.StatusCode;
 
-public interface HttpStatusConverter {
+// https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/trace/semantic_conventions/http.md#status
+enum HttpStatusConverter {
+  SERVER {
+    @Override
+    StatusCode statusFromHttpStatus(int httpStatus) {
+      if (httpStatus >= 100 && httpStatus < 500) {
+        return StatusCode.UNSET;
+      }
 
-  HttpStatusConverter SERVER = HttpServerStatusConverter.INSTANCE;
-  HttpStatusConverter CLIENT = HttpClientStatusConverter.INSTANCE;
+      return StatusCode.ERROR;
+    }
+  },
+  CLIENT {
+    @Override
+    StatusCode statusFromHttpStatus(int httpStatus) {
+      if (httpStatus >= 100 && httpStatus < 400) {
+        return StatusCode.UNSET;
+      }
 
-  StatusCode statusFromHttpStatus(int httpStatus);
+      return StatusCode.ERROR;
+    }
+  };
+
+  abstract StatusCode statusFromHttpStatus(int httpStatus);
 }