[TESTS] createUser via the user model helper for integration tests

(cherry picked from commit c1d14c5fff)
(cherry picked from commit e0e8aabc98)
(cherry picked from commit 392a415070)
(cherry picked from commit c7cf1307ca)
(cherry picked from commit 93b13d092b)

[TESTS] createUser via the user model helper for integration tests (squash)

(cherry picked from commit 6ff2383952)
(cherry picked from commit de2a6fe8c3)
(cherry picked from commit 398a6ab072)
(cherry picked from commit 16abc89780)
(cherry picked from commit 312a3ec5d9)
(cherry picked from commit 85c6d8e290)
(cherry picked from commit 79150d30a4)
(cherry picked from commit 436137962d)

tests/integration/integration_test.go

@@ -23,7 +23,9 @@ import (
 	"time"
 
 	"code.gitea.io/gitea/models/auth"
+	"code.gitea.io/gitea/models/db"
 	"code.gitea.io/gitea/models/unittest"
+	user_model "code.gitea.io/gitea/models/user"
 	gitea_context "code.gitea.io/gitea/modules/context"
 	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/json"
@@ -33,6 +35,7 @@ import (
 	"code.gitea.io/gitea/modules/util"
 	"code.gitea.io/gitea/modules/web"
 	"code.gitea.io/gitea/routers"
+	user_service "code.gitea.io/gitea/services/user"
 	"code.gitea.io/gitea/tests"
 
 	"github.com/PuerkitoBio/goquery"
@@ -228,6 +231,22 @@ func getUserToken(t testing.TB, userName string, scope ...auth.AccessTokenScope)
 	return getTokenForLoggedInUser(t, loginUser(t, userName), scope...)
 }
 
+func createUser(ctx context.Context, t testing.TB, user *user_model.User) func() {
+	user.MustChangePassword = false
+	user.LowerName = strings.ToLower(user.Name)
+
+	assert.NoError(t, db.Insert(ctx, user))
+
+	if len(user.Email) > 0 {
+		changePrimaryEmail := true
+		assert.NoError(t, user_model.UpdateUser(ctx, user, changePrimaryEmail))
+	}
+
+	return func() {
+		assert.NoError(t, user_service.DeleteUser(ctx, user, true))
+	}
+}
+
 func loginUser(t testing.TB, userName string) *TestSession {
 	t.Helper()