fix(session): an extra check for session log (#37508)

Author: pavelfeldman

packages/playwright/src/mcp/browser/sessionLog.ts

@@ -79,7 +79,7 @@ export class SessionLog {
     code = code.trim();
     if (isUpdate) {
       const lastEntry = this._pendingEntries[this._pendingEntries.length - 1];
-      if (lastEntry.userAction?.name === action.name) {
+      if (lastEntry?.userAction?.name === action.name) {
         lastEntry.userAction = action;
         lastEntry.code = code;
         return;