Document the `sync` option for revoke/revoke-prefix. (#11538)

website/content/api-docs/system/leases.mdx

@@ -137,6 +137,9 @@ This endpoint revokes a lease immediately.
 ### Parameters
 
 - `lease_id` `(string: <required>)` – Specifies the ID of the lease to revoke.
+- `sync` `(bool: false)` - Instead of the default behaviour of queueing the lease
+  revocation, sync=true will revoke the lease immediately and only return once
+  complete.
 
 ### Sample Payload
 
@@ -205,6 +208,9 @@ used to revoke very large numbers of secrets/tokens at once.
 
 - `prefix` `(string: <required>)` – Specifies the prefix to revoke. This is
   specified as part of the URL.
+- `sync` `(bool: false)` - Instead of the default behaviour of queueing the lease
+revocations, sync=true will revoke ths leases immediately and only return once
+complete.
 
 ### Sample Request
 

website/content/docs/commands/lease/revoke.mdx

@@ -40,3 +40,6 @@ flags](/docs/commands) included on all commands.
 
 - `-prefix` `(bool: false)` - Treat the ID as a prefix instead of an exact lease
   ID. This can revoke multiple leases simultaneously. The default is false.
+
+- `-sync` `(bool: false)` - Make the operation synchronous instead of queuing the
+revocations to be done in the background.