fix: app data为空设为null

server/src/main/java/com/pica/cloud/online/exam/analysis/server/controller/AnalysisController.java

@@ -402,7 +402,7 @@ public class AnalysisController {
     @ApiOperation(value = "回复", response = PicaResponse.class)
     @RequestMapping(value = "/reply/{examTitleId}", method = RequestMethod.POST, produces = "application/json;charset=UTF-8")
     public PicaResponse reply( @PathVariable("examTitleId") Integer examTitleId,
-                               @RequestParam String content,
+                               @RequestBody String content,
                                @RequestHeader String token) {
         if (token == null) {
             PicaResponse picaResponse = ReturnUtil.getPicaResponse(PicaResultCode.SYSTEM_NO_TOKEN);