feat: add documentation for single active replication

docs/administration/configuring-replication/create-replication-rules.md

@@ -82,6 +82,9 @@ You **can not** replicate from Harbor v1.x to v2.0 and later, and you **can not*
    {{< note >}}
    Copy by chunk has not been verified officially between harbor and other type registries. The default chunk size is 10MB, you can override it by setting env `REPLICATION_CHUNK_SIZE` in the jobservice, the value should be united as bytes, for example `10MB=1024*1024*10` then you should set `REPLICATION_CHUNK_SIZE=10485760`.
    {{< /note >}}
+1. Optionally select the Single active replication checkbox to enable skipping of executions until the previous active execution finishes, avoiding the execution of the same replication rules multiple times in parallel.
+   ![Single active replication](../../../img/replication-rule10.png)
+
 1. Click **Save** to create the replication rule.
 
 ## What to Do Next