feat: "更新getAssignmentById的请求方式"

src/main/java/com/njuzr/eaibackend/controller/AssignmentController.java

@@ -77,9 +77,9 @@ public class AssignmentController {
         return MyResponse.success(assignmentService.findAssignmentPage(page, assignmentQueryDTO));
     }
 
-    @GetMapping("/{assignmentId}")
+    @GetMapping
     public MyResponse getAssignmentById(
-            @PathVariable Long assignmentId
+            @RequestParam Long assignmentId
     ) {
         return MyResponse.success(assignmentService.findAssignmentById(assignmentId));
     }