Remove commit status running and warning to align GitHub (#25839)

Fix #25776. Close #25826.

In the discussion of #25776, @wolfogre's suggestion was to remove the
commit status of `running` and `warning` to keep it consistent with
github.

references:
-
https://docs.github.com/en/rest/commits/statuses?apiVersion=2022-11-28#about-commit-statuses


## ⚠️ BREAKING ⚠️

So the commit status of Gitea will be consistent with GitHub, only
`pending`, `success`, `error` and `failure`, while `warning` and
`running` are not supported anymore.

---------

Co-authored-by: Jason Song <i@wolfogre.com>

models/migrations/migrations.go

@@ -513,6 +513,8 @@ var migrations = []Migration{
 	NewMigration("Add branch table", v1_21.AddBranchTable),
 	// v265 -> v266
 	NewMigration("Alter Actions Artifact table", v1_21.AlterActionArtifactTable),
+	// v266 -> v267
+	NewMigration("Reduce commit status", v1_21.ReduceCommitStatus),
 }
 
 // GetCurrentDBVersion returns the current db version

models/migrations/v1_21/v266.go

@@ -0,0 +1,26 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package v1_21 //nolint
+
+import (
+	"xorm.io/xorm"
+)
+
+func ReduceCommitStatus(x *xorm.Engine) error {
+	sess := x.NewSession()
+	defer sess.Close()
+
+	if err := sess.Begin(); err != nil {
+		return err
+	}
+
+	if _, err := sess.Exec(`UPDATE commit_status SET state='pending' WHERE state='running'`); err != nil {
+		return err
+	}
+	if _, err := sess.Exec(`UPDATE commit_status SET state='failure' WHERE state='warning'`); err != nil {
+		return err
+	}
+
+	return sess.Commit()
+}