[MM-45817] Set cloud cookies whenever user gets logged in (#20692)

app/login.go

@@ -331,6 +331,11 @@ func (a *App) AttachSessionCookies(c *request.Context, w http.ResponseWriter, r
 	http.SetCookie(w, sessionCookie)
 	http.SetCookie(w, userCookie)
 	http.SetCookie(w, csrfCookie)
+
+	// For context see: https://mattermost.atlassian.net/browse/MM-39583
+	if a.Channels().License() != nil && *a.Channels().License().Features.Cloud {
+		a.AttachCloudSessionCookie(c, w, r)
+	}
 }
 
 func GetProtocol(r *http.Request) string {