fix: respect Accept headers during maintenance mode #18057 (#18063)

(cherry picked from commit 022df94711)

Co-authored-by: Ankush Menat <ankush@frappe.io>

frappe/app.py

@@ -83,9 +83,6 @@ def application(request: Request):
 	except HTTPException as e:
 		return e
 
-	except frappe.SessionStopped as e:
-		response = frappe.utils.response.handle_session_stopped()
-
 	except Exception as e:
 		response = handle_exception(e)
 
@@ -228,6 +225,9 @@ def handle_exception(e):
 		# if the request is ajax, send back the trace or error message
 		response = frappe.utils.response.report_error(http_status_code)
 
+	elif isinstance(e, frappe.SessionStopped):
+		response = frappe.utils.response.handle_session_stopped()
+
 	elif (
 		http_status_code == 500
 		and (frappe.db and isinstance(e, frappe.db.InternalError))