Merge pull request #38220 from Arhell/pt-cer

[pt] Document generating SHA256 CA certificate

Author: k8s-ci-robot

content/pt-br/docs/concepts/cluster-administration/certificates.md

@@ -103,7 +103,7 @@ manualmente através `easyrsa`, `openssl` ou `cfssl`.
 
         openssl x509 -req -in server.csr -CA ca.crt -CAkey ca.key \
         -CAcreateserial -out server.crt -days 10000 \
-        -extensions v3_ext -extfile csr.conf
+        -extensions v3_ext -extfile csr.conf -sha256
 1.  Veja o certificado:
 
         openssl x509  -noout -text -in ./server.crt