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/organization/org_user_test.go

@@ -131,7 +131,7 @@ func TestAddOrgUser(t *testing.T) {
 	testSuccess := func(orgID, userID int64, isPublic bool) {
 		org := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: orgID})
 		expectedNumMembers := org.NumMembers
-		if !unittest.BeanExists(t, &organization.OrgUser{OrgID: orgID, UID: userID}) {
+		if unittest.GetBean(t, &organization.OrgUser{OrgID: orgID, UID: userID}) == nil {
 			expectedNumMembers++
 		}
 		assert.NoError(t, organization.AddOrgUser(db.DefaultContext, orgID, userID))