Refactor tests (#33021)

1. fix incorrect tests, for example: BeanExists doesn't do assert and
shouldn't be used
2. remove unnecessary test functions
3. introduce DumpQueryResult to help to see the database rows during
test (at least I need it)

```
====== DumpQueryResult: SELECT * FROM action_runner_token ======
- # row[0]
  id: 1
  token: xeiWBL5kuTYxGPynHCqQdoeYmJAeG3IzGXCYTrDX
  owner_id: 0
...
```

models/activities/user_heatmap_test.go

@@ -64,11 +64,9 @@ func TestGetUserHeatmapDataByUser(t *testing.T) {
 	for _, tc := range testCases {
 		user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: tc.userID})
 
-		doer := &user_model.User{ID: tc.doerID}
-		_, err := unittest.LoadBeanIfExists(doer)
-		assert.NoError(t, err)
-		if tc.doerID == 0 {
-			doer = nil
+		var doer *user_model.User
+		if tc.doerID != 0 {
+			doer = unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: tc.doerID})
 		}
 
 		// get the action for comparison