MM-40817: Use license interface in Channels (#19678)

* MM-40817: Use license interface in Channels

https://mattermost.atlassian.net/browse/MM-40817

```release-note
NONE
```

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

api4/config.go

@@ -67,7 +67,7 @@ func getConfig(c *Context, w http.ResponseWriter, r *http.Request) {
 	auditRec.Success()
 
 	w.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
-	if c.App.Srv().License() != nil && *c.App.Srv().License().Features.Cloud {
+	if c.App.Channels().License() != nil && *c.App.Channels().License().Features.Cloud {
 		js, jsonErr := cfg.ToJSONFiltered(model.ConfigAccessTagType, model.ConfigAccessTagCloudRestrictable)
 		if jsonErr != nil {
 			c.Err = model.NewAppError("getConfig", "api.marshal_error", nil, jsonErr.Error(), http.StatusInternalServerError)
@@ -180,7 +180,7 @@ func updateConfig(c *Context, w http.ResponseWriter, r *http.Request) {
 	c.LogAudit("updateConfig")
 
 	w.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
-	if c.App.Srv().License() != nil && *c.App.Srv().License().Features.Cloud {
+	if c.App.Channels().License() != nil && *c.App.Channels().License().Features.Cloud {
 		js, jsonErr := cfg.ToJSONFiltered(model.ConfigAccessTagType, model.ConfigAccessTagCloudRestrictable)
 		if jsonErr != nil {
 			c.Err = model.NewAppError("updateConfig", "api.marshal_error", nil, jsonErr.Error(), http.StatusInternalServerError)
@@ -306,7 +306,7 @@ func patchConfig(c *Context, w http.ResponseWriter, r *http.Request) {
 	}
 
 	w.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
-	if c.App.Srv().License() != nil && *c.App.Srv().License().Features.Cloud {
+	if c.App.Channels().License() != nil && *c.App.Channels().License().Features.Cloud {
 		js, jsonErr := cfg.ToJSONFiltered(model.ConfigAccessTagType, model.ConfigAccessTagCloudRestrictable)
 		if jsonErr != nil {
 			c.Err = model.NewAppError("patchConfig", "api.marshal_error", nil, jsonErr.Error(), http.StatusInternalServerError)