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/unittest/unit_tests.go

@@ -4,13 +4,17 @@
 package unittest
 
 import (
+	"fmt"
 	"math"
+	"os"
+	"strings"
 
 	"code.gitea.io/gitea/models/db"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"xorm.io/builder"
+	"xorm.io/xorm"
 )
 
 // Code in this file is mainly used by unittest.CheckConsistencyFor, which is not in the unit test for various reasons.
@@ -51,22 +55,23 @@ func whereOrderConditions(e db.Engine, conditions []any) db.Engine {
 	return e.OrderBy(orderBy)
 }
 
-// LoadBeanIfExists loads beans from fixture database if exist
-func LoadBeanIfExists(bean any, conditions ...any) (bool, error) {
+func getBeanIfExists(bean any, conditions ...any) (bool, error) {
 	e := db.GetEngine(db.DefaultContext)
 	return whereOrderConditions(e, conditions).Get(bean)
 }
 
-// BeanExists for testing, check if a bean exists
-func BeanExists(t assert.TestingT, bean any, conditions ...any) bool {
-	exists, err := LoadBeanIfExists(bean, conditions...)
-	assert.NoError(t, err)
-	return exists
+func GetBean[T any](t require.TestingT, bean T, conditions ...any) (ret T) {
+	exists, err := getBeanIfExists(bean, conditions...)
+	require.NoError(t, err)
+	if exists {
+		return bean
+	}
+	return ret
 }
 
 // AssertExistsAndLoadBean assert that a bean exists and load it from the test database
 func AssertExistsAndLoadBean[T any](t require.TestingT, bean T, conditions ...any) T {
-	exists, err := LoadBeanIfExists(bean, conditions...)
+	exists, err := getBeanIfExists(bean, conditions...)
 	require.NoError(t, err)
 	require.True(t, exists,
 		"Expected to find %+v (of type %T, with conditions %+v), but did not",
@@ -112,25 +117,11 @@ func GetCount(t assert.TestingT, bean any, conditions ...any) int {
 
 // AssertNotExistsBean assert that a bean does not exist in the test database
 func AssertNotExistsBean(t assert.TestingT, bean any, conditions ...any) {
-	exists, err := LoadBeanIfExists(bean, conditions...)
+	exists, err := getBeanIfExists(bean, conditions...)
 	assert.NoError(t, err)
 	assert.False(t, exists)
 }
 
-// AssertExistsIf asserts that a bean exists or does not exist, depending on
-// what is expected.
-func AssertExistsIf(t assert.TestingT, expected bool, bean any, conditions ...any) {
-	exists, err := LoadBeanIfExists(bean, conditions...)
-	assert.NoError(t, err)
-	assert.Equal(t, expected, exists)
-}
-
-// AssertSuccessfulInsert assert that beans is successfully inserted
-func AssertSuccessfulInsert(t assert.TestingT, beans ...any) {
-	err := db.Insert(db.DefaultContext, beans...)
-	assert.NoError(t, err)
-}
-
 // AssertCount assert the count of a bean
 func AssertCount(t assert.TestingT, bean, expected any) bool {
 	return assert.EqualValues(t, expected, GetCount(t, bean))
@@ -155,3 +146,39 @@ func AssertCountByCond(t assert.TestingT, tableName string, cond builder.Cond, e
 	return assert.EqualValues(t, expected, GetCountByCond(t, tableName, cond),
 		"Failed consistency test, the counted bean (of table %s) was %+v", tableName, cond)
 }
+
+// DumpQueryResult dumps the result of a query for debugging purpose
+func DumpQueryResult(t require.TestingT, sqlOrBean any, sqlArgs ...any) {
+	x := db.GetEngine(db.DefaultContext).(*xorm.Engine)
+	goDB := x.DB().DB
+	sql, ok := sqlOrBean.(string)
+	if !ok {
+		sql = fmt.Sprintf("SELECT * FROM %s", db.TableName(sqlOrBean))
+	} else if !strings.Contains(sql, " ") {
+		sql = fmt.Sprintf("SELECT * FROM %s", sql)
+	}
+	rows, err := goDB.Query(sql, sqlArgs...)
+	require.NoError(t, err)
+	defer rows.Close()
+	columns, err := rows.Columns()
+	require.NoError(t, err)
+
+	_, _ = fmt.Fprintf(os.Stdout, "====== DumpQueryResult: %s ======\n", sql)
+	idx := 0
+	for rows.Next() {
+		row := make([]any, len(columns))
+		rowPointers := make([]any, len(columns))
+		for i := range row {
+			rowPointers[i] = &row[i]
+		}
+		require.NoError(t, rows.Scan(rowPointers...))
+		_, _ = fmt.Fprintf(os.Stdout, "- # row[%d]\n", idx)
+		for i, col := range columns {
+			_, _ = fmt.Fprintf(os.Stdout, "  %s: %v\n", col, row[i])
+		}
+		idx++
+	}
+	if idx == 0 {
+		_, _ = fmt.Fprintf(os.Stdout, "(no result, columns: %s)\n", strings.Join(columns, ", "))
+	}
+}