controller-runtime: update README.md

[nakamasato]

Changes in controller-runtime@v0.15.0

• https://github.com/kubernetes-sigs/controller-runtime/releases/tag/v0.15.0

  • ⚠️ Refactor source/handler/predicate packages to remove dep injection kubernetes-sigs/controller-runtime#2120

-       kindWithCacheMysqlUser := source.NewKindWithCache(mysqluser, cache)
-       kindWithCacheMysql := source.NewKindWithCache(mysql, cache)
-       kindWithCachesecret := source.NewKindWithCache(secret, cache)
+       kindWithCacheMysqlUser := source.Kind(cache, mysqluser)
+       kindWithCacheMysql := source.Kind(cache, mysql)
+       kindWithCachesecret := source.Kind(cache, secret)

Changes in controller-runtime@v0.16.0

• https://github.com/kubernetes-sigs/controller-runtime/releases/tag/v0.16.0

  • ⚠ Introduce Metrics Options struct & secure metrics serving kubernetes-sigs/controller-runtime#2407

import (
+ metricsserver "sigs.k8s.io/controller-runtime/pkg/metrics/server"
)
- MetricsBindAddress: metricsAddr
+ Metrics: metricsserver.Options{BindAddress: metricsAddr},

• ⚠ Remove deprecated manager, webhook and cluster options kubernetes-sigs/controller-runtime#2422