remove ocsp for letsencrypt server

acme.sh

@@ -5504,6 +5504,13 @@ renew() {
   if [ -z "$Le_Keylength" ]; then
     Le_Keylength=2048
   fi
+  if [ "$CA_LETSENCRYPT_V2" = "$Le_API" ]; then
+    #letsencrypt doesn't support ocsp anymore
+    if [ "$Le_OCSP_Staple" ]; then
+      export Le_OCSP_Staple=""
+      _cleardomainconf Le_OCSP_Staple
+    fi
+  fi
   issue "$Le_Webroot" "$Le_Domain" "$Le_Alt" "$Le_Keylength" "$Le_RealCertPath" "$Le_RealKeyPath" "$Le_RealCACertPath" "$Le_ReloadCmd" "$Le_RealFullChainPath" "$Le_PreHook" "$Le_PostHook" "$Le_RenewHook" "$Le_LocalAddress" "$Le_ChallengeAlias" "$Le_Preferred_Chain" "$Le_Valid_From" "$Le_Valid_To"
   res="$?"
   if [ "$res" != "0" ]; then