Fixed errcheck issues in server/channels/app/integration_action_test.go (#29039)

Co-authored-by: Ben Schumacher <ben.schumacher@mattermost.com>

server/.golangci.yml

@@ -93,7 +93,6 @@ issues:
         channels/app/import_functions.go|\
         channels/app/imports/import_validators.go|\
         channels/app/integration_action.go|\
-        channels/app/integration_action_test.go|\
         channels/app/job_test.go|\
         channels/app/migrations.go|\
         channels/app/permissions.go|\

server/channels/app/integration_action_test.go

@@ -582,9 +582,11 @@ func TestSubmitInteractiveDialog(t *testing.T) {
 			Errors: map[string]string{"name1": "some error"},
 		}
 
-		b, _ := json.Marshal(resp)
+		b, err := json.Marshal(resp)
+		require.NoError(t, err)
 
-		w.Write(b)
+		_, err = w.Write(b)
+		require.NoError(t, err)
 	}))
 	defer ts.Close()