Add renewBefore in docs / example code

Author: titanlien

docs/usage/tutorials/gateway-api-gateways.md

@@ -51,6 +51,7 @@ metadata:
   annotations:
     #cert.gardener.cloud/dnsnames: "*.example.com" # alternative if you want to control the dns names explicitly.
     cert.gardener.cloud/purpose: managed
+    #cert.gardener.cloud/renew-before: "720h"      # optional to specify when to renew the certificate before expiration (default: 720h/30 days, min: 5m, max: duration-5m)
 spec:
   gatewayClassName: istio
   listeners:

docs/usage/tutorials/istio-gateways.md

@@ -55,6 +55,7 @@ metadata:
     cert.gardener.cloud/purpose: managed
     #cert.gardener.cloud/dnsnames: "*.example.com"                # alternative if you want to control the dns names explicitly.
     #cert.gardener.cloud/secret-namespace: "istio-system"         # optional to specify the namespace where the certificate secret should be created
+    #cert.gardener.cloud/renew-before: "720h"                     # optional to specify when to renew the certificate before expiration (default: 720h/30 days, min: 5m, max: duration-5m)
 spec:
   selector:
     istio: ingressgateway # use Istio default gateway implementation

examples/40-ingress-echoheaders.yaml

@@ -19,6 +19,7 @@ metadata:
     #cert.gardener.cloud/private-key-algorithm: ECDSA             # optional to specify algorithm for private key, allowed values are 'RSA' or 'ECDSA'
     #cert.gardener.cloud/private-key-size: "384"                  # optional to specify size of private key, allowed values for RSA are "2048", "3072", "4096" and for ECDSA "256" and "384"
     #cert.gardener.cloud/private-key-encoding: PKCS8              # optional to specify encoding for private key, allowed values are 'PKCS1' (default) or 'PKCS8'
+    #cert.gardener.cloud/renew-before: 720h                      # optional to specify when to renew the certificate before expiration (default is 720h/30 days)
     # annotations needed when using DNSRecords
     #cert.gardener.cloud/dnsrecord-provider-type: aws-route53
     #cert.gardener.cloud/dnsrecord-secret-ref: myns/mysecret