Secrets storage with SecretKey encrypted (#22142)

Fork of #14483, but [gave up
MasterKey](https://github.com/go-gitea/gitea/pull/14483#issuecomment-1350728557),
and fixed some problems.

Close #12065.
Needed by #13539.

Featrues:
- Secrets for repo and org, not user yet.
- Use SecretKey to encrypte/encrypt secrets.
- Trim spaces of secret value.
- Add a new locale ini block, to make it easy to support secrets for
user.

Snapshots:

Repo level secrets:

![image](https://user-images.githubusercontent.com/9418365/207823319-b8a4903f-38ca-4af7-9d05-336a5af906f3.png)

Rrg level secrets

![image](https://user-images.githubusercontent.com/9418365/207823371-8bd02e93-1928-40d1-8c76-f48b255ace36.png)

Co-authored-by: Lauris BH <lauris@nix.lv>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: delvh <dev.lh@web.de>
Co-authored-by: KN4CK3R <admin@oldschoolhack.me>

routers/web/web.go

@@ -774,6 +774,12 @@ func RegisterRoutes(m *web.Route) {
 					m.Post("/initialize", web.Bind(forms.InitializeLabelsForm{}), org.InitializeLabels)
 				})
 
+				m.Group("/secrets", func() {
+					m.Get("", org.Secrets)
+					m.Post("", web.Bind(forms.AddSecretForm{}), org.SecretsPost)
+					m.Post("/delete", org.SecretsDelete)
+				})
+
 				m.Route("/delete", "GET,POST", org.SettingsDelete)
 
 				m.Group("/packages", func() {
@@ -912,6 +918,10 @@ func RegisterRoutes(m *web.Route) {
 				m.Combo("").Get(repo.DeployKeys).
 					Post(web.Bind(forms.AddKeyForm{}), repo.DeployKeysPost)
 				m.Post("/delete", repo.DeleteDeployKey)
+				m.Group("/secrets", func() {
+					m.Post("", web.Bind(forms.AddSecretForm{}), repo.SecretsPost)
+					m.Post("/delete", repo.DeleteSecret)
+				})
 			})
 
 			m.Group("/lfs", func() {