add comment for azure-functions using v1 as default schema version

Author: duncanpharvey

internal-api/src/main/java/datadog/trace/api/Config.java

@@ -3746,6 +3746,7 @@ private Map<String, String> getAzureAppServicesTags() {
 
   private int schemaVersionFromConfig() {
     String defaultVersion;
+    // use v1 so Azure Functions operation name is consistent with that of other tracers
     if (azureFunctions) {
       defaultVersion = "v1";
     } else {