fix: link to memcached_controller.go (#4973)

Fix the link to memcached_controller.go to point to master.

Signed-off-by: varshaprasad96 <[email protected]>

Author: varshaprasad96

website/content/en/docs/building-operators/golang/tutorial.md

@@ -466,7 +466,7 @@ Next, check out the following:
 [generating-crd]: https://book.kubebuilder.io/reference/generating-crd.html
 [markers]: https://book.kubebuilder.io/reference/markers.html
 [crd-markers]: https://book.kubebuilder.io/reference/markers/crd-validation.html
-[memcached_controller]: https://github.com/operator-framework/operator-sdk/blob/v1.3.0/testdata/go/v3/memcached-operator/controllers/memcached_controller.go
+[memcached_controller]: https://github.com/operator-framework/operator-sdk/blob/latest/testdata/go/v3/memcached-operator/controllers/memcached_controller.go
 [builder_godocs]: https://pkg.go.dev/sigs.k8s.io/controller-runtime/pkg/builder#example-Builder
 [activate_modules]: https://github.com/golang/go/wiki/Modules#how-to-install-and-activate-module-support
 [advanced-topics]: /docs/building-operators/golang/advanced-topics/