Remove outdated code about fixture generation (#32708)

(cherry picked from commit e45ffc530f482a46de25d28f18b039f296750414)

Conflicts:
	models/fixture_test.go
  trivial context conflict and remove one line in deadcode

contrib/fixtures/fixture_generation.go

@@ -1,80 +0,0 @@
-// Copyright 2020 The Gitea Authors. All rights reserved.
-// SPDX-License-Identifier: MIT
-
-//nolint:forbidigo
-package main
-
-import (
-	"context"
-	"fmt"
-	"os"
-	"path/filepath"
-
-	"code.gitea.io/gitea/models"
-	"code.gitea.io/gitea/models/unittest"
-)
-
-// To generate derivative fixtures, execute the following from Gitea's repository base dir:
-// go run -tags 'sqlite sqlite_unlock_notify' contrib/fixtures/fixture_generation.go [fixture...]
-
-var (
-	generators = []struct {
-		gen  func(ctx context.Context) (string, error)
-		name string
-	}{
-		{
-			models.GetYamlFixturesAccess, "access",
-		},
-	}
-	fixturesDir string
-)
-
-func main() {
-	pathToGiteaRoot := "."
-	fixturesDir = filepath.Join(pathToGiteaRoot, "models", "fixtures")
-	if err := unittest.CreateTestEngine(unittest.FixturesOptions{
-		Dir: fixturesDir,
-	}); err != nil {
-		fmt.Printf("CreateTestEngine: %+v", err)
-		os.Exit(1)
-	}
-	if err := unittest.PrepareTestDatabase(); err != nil {
-		fmt.Printf("PrepareTestDatabase: %+v\n", err)
-		os.Exit(1)
-	}
-	ctx := context.Background()
-	if len(os.Args) == 0 {
-		for _, r := range os.Args {
-			if err := generate(ctx, r); err != nil {
-				fmt.Printf("generate '%s': %+v\n", r, err)
-				os.Exit(1)
-			}
-		}
-	} else {
-		for _, g := range generators {
-			if err := generate(ctx, g.name); err != nil {
-				fmt.Printf("generate '%s': %+v\n", g.name, err)
-				os.Exit(1)
-			}
-		}
-	}
-}
-
-func generate(ctx context.Context, name string) error {
-	for _, g := range generators {
-		if g.name == name {
-			data, err := g.gen(ctx)
-			if err != nil {
-				return err
-			}
-			path := filepath.Join(fixturesDir, name+".yml")
-			if err := os.WriteFile(path, []byte(data), 0o644); err != nil {
-				return fmt.Errorf("%s: %+v", path, err)
-			}
-			fmt.Printf("%s created.\n", path)
-			return nil
-		}
-	}
-
-	return fmt.Errorf("generator not found")
-}