Added/updated snippets for docs (#2318)

docs/doc_examples/a428d518162918733d49261ffd65cfc1.asciidoc

@@ -0,0 +1,20 @@
+// This file is autogenerated, DO NOT EDIT
+// Use `node scripts/generate-docs-examples.js` to generate the docs examples
+
+[source, js]
+----
+const response = await client.indices.create({
+  index: "custom_unique_example",
+  settings: {
+    analysis: {
+      analyzer: {
+        standard_truncate: {
+          tokenizer: "standard",
+          filter: ["unique"],
+        },
+      },
+    },
+  },
+});
+console.log(response);
+----