Disable federation by default (#20045) (#20046)

* Disable federation by default (#20045)

- Backport #20045
  - A Gitea instance should choose whetever they want to federate(as once it has more features also brings extra costs/moderation/unexpected behavior) with other AP/ForgeFed software.

* Fix tests

integrations/api_nodeinfo_test.go

@@ -11,17 +11,20 @@ import (
 
 	"code.gitea.io/gitea/modules/setting"
 	api "code.gitea.io/gitea/modules/structs"
+	"code.gitea.io/gitea/routers"
 
 	"github.com/stretchr/testify/assert"
 )
 
 func TestNodeinfo(t *testing.T) {
-	onGiteaRun(t, func(*testing.T, *url.URL) {
-		setting.Federation.Enabled = true
-		defer func() {
-			setting.Federation.Enabled = false
-		}()
+	setting.Federation.Enabled = true
+	c = routers.NormalRoutes()
+	defer func() {
+		setting.Federation.Enabled = false
+		c = routers.NormalRoutes()
+	}()
 
+	onGiteaRun(t, func(*testing.T, *url.URL) {
 		req := NewRequestf(t, "GET", "/api/v1/nodeinfo")
 		resp := MakeRequest(t, req, http.StatusOK)
 		var nodeinfo api.NodeInfo