Fixed some ineffective assignments (#12543)

app/bot_test.go

@@ -632,6 +632,7 @@ func TestSetBotIconImage(t *testing.T) {
 			Username: "username",
 			Id:       th.BasicUser.Id,
 		})
+		require.Nil(t, err)
 		defer th.App.PermanentDeleteBot(bot.UserId)
 
 		fpath := fmt.Sprintf("/bots/%v/icon.svg", bot.UserId)
@@ -683,6 +684,7 @@ func TestGetBotIconImage(t *testing.T) {
 			Username: "username",
 			Id:       th.BasicUser.Id,
 		})
+		require.Nil(t, err)
 		defer th.App.PermanentDeleteBot(bot.UserId)
 
 		svgFile.Seek(0, 0)
@@ -729,6 +731,7 @@ func TestDeleteBotIconImage(t *testing.T) {
 			Username: "username",
 			Id:       th.BasicUser.Id,
 		})
+		require.Nil(t, err)
 		defer th.App.PermanentDeleteBot(bot.UserId)
 
 		// Set icon