Add get_similar_documents code-sample

Author: ellnix

.code-samples.meilisearch.yaml

@@ -742,3 +742,5 @@ update_localized_attribute_settings_1: |-
   ])
 reset_localized_attribute_settings_1: |-
   client.index('INDEX_NAME').reset_localized_attributes()
+get_similar_post_1: |-
+  client.index("INDEX_NAME").get_similar_documents({"id": "TARGET_DOCUMENT_ID", "embedder": "default"})