fix: Bring back private keys logging (#1481)

**Description of the change**

- Fixes missing log entries in the doc

https://github.com/bitnami-labs/sealed-secrets/blob/main/docs/bring-your-own-certificates.md#see-the-new-certificates-private-keys-in-the-controller-logs

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**Applicable issues**

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- fixes
40c279f#r139767674

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Signed-off-by: Ivan Sabelnikov <ivan@mapped.com>

docs/bring-your-own-certificates.md

@@ -44,8 +44,8 @@ kubectl -n "$NAMESPACE" logs -l name=sealed-secrets-controller
 controller version: v0.12.1+dirty
 2020/06/09 14:30:45 Starting sealed-secrets controller version: v0.12.1+dirty
 2020/06/09 14:30:45 Searching for existing private keys
-2020/06/09 14:30:45 ----- sealed-secrets-key5rxd9
-2020/06/09 14:30:45 ----- mycustomkeys
+2020/06/09 14:30:45 registered private key secretname=sealed-secrets-key5rxd9
+2020/06/09 14:30:45 registered private key secretname=mycustomkeys
 2020/06/09 14:30:45 HTTP server serving on :8080
 ```
 

pkg/controller/main.go

@@ -90,6 +90,7 @@ func initKeyRegistry(ctx context.Context, client kubernetes.Interface, r io.Read
 		if err := keyRegistry.registerNewKey(secret.Name, key, certs[0], certs[0].NotBefore); err != nil {
 			return nil, err
 		}
+		slog.Info("registered private key", "secretname", secret.Name)
 	}
 	return keyRegistry, nil
 }