Ensure settings for Service and Mailer are read on the install page

NewContext does not set the mailer or service settings so add
a new function that will run this.

Fix #15894

Signed-off-by: Andrew Thornton <[email protected]>

Author: zeripath

modules/setting/setting.go

@@ -1179,3 +1179,8 @@ func NewServices() {
 	newProject()
 	newMimeTypeMap()
 }
+
+func NewServicesForInstall() {
+	newService()
+	newMailService()
+}

routers/init.go

@@ -100,6 +100,7 @@ func PreInstallInit(ctx context.Context) bool {
 			log.Info("SQLite3 Supported")
 		}
 		setting.InitDBConfig()
+		setting.NewServicesForInstall()
 		svg.Init()
 	}