feat: Add Cancel Query Nerdgraph Block

src/content/docs/apis/nerdgraph/examples/async-queries-nrql-tutorial.mdx

@@ -68,3 +68,18 @@ Some important details about this query:
 * The `account` argument must match the `account` argument from the original query.
 * This query will return results if asynchronous execution has completed; otherwise it will return `queryProgress` data.
 * The query can be repeated verbatim until results or an error are returned.
+
+## Cancel an async query [#example-cancel-query]
+
+You can cancel an asynchronous query by using the `cancelQuery` mutation. This mutation takes the `queryId` of the
+query you want to cancel. It will either return an `ACCEPTED` status, or `REJECTED` status with a reason for rejection.
+
+```graphql
+mutation {
+  cancelQuery(queryId: "YOUR_QUERY_ID") {
+    queryId
+    requestStatus
+    rejectionReason
+  }
+}
+```