fix: handle missing span_name in logging test assertions (#2665)

lib/runtime/src/logging.rs

@@ -1009,30 +1009,42 @@ pub mod tests {
 
                 // Parent span has no parent_id
                 for log_line in &lines {
-                    if log_line.get("span_name").unwrap().as_str().unwrap() == "parent" {
+                    if let Some(span_name) = log_line.get("span_name") {
+                        if let Some(span_name_str) = span_name.as_str() {
+                            if span_name_str == "parent" {
                                 assert!(log_line.get("parent_id").is_none());
                             }
                         }
+                    }
+                }
 
                 // Child span's parent_id is parent_span_id
                 for log_line in &lines {
-                    if log_line.get("span_name").unwrap().as_str().unwrap() == "child" {
+                    if let Some(span_name) = log_line.get("span_name") {
+                        if let Some(span_name_str) = span_name.as_str() {
+                            if span_name_str == "child" {
                                 assert_eq!(
                                     log_line.get("parent_id").unwrap().as_str().unwrap(),
                                     &parent_span_id
                                 );
                             }
                         }
+                    }
+                }
 
                 // Grandchild span's parent_id is child_span_id
                 for log_line in &lines {
-                    if log_line.get("span_name").unwrap().as_str().unwrap() == "grandchild" {
+                    if let Some(span_name) = log_line.get("span_name") {
+                        if let Some(span_name_str) = span_name.as_str() {
+                            if span_name_str == "grandchild" {
                                 assert_eq!(
                                     log_line.get("parent_id").unwrap().as_str().unwrap(),
                                     &child_span_id
                                 );
                             }
                         }
+                    }
+                }
 
                 // Validate duration relationships
                 let parent_duration = lines