docs: add config doc block for retry config

Author: AllanZhengYP

packages/retry-middleware/src/configurations.ts

@@ -3,7 +3,13 @@ import { ExponentialBackOffStrategy } from "./defaultStrategy";
 
 export namespace RetryConfig {
   export interface Input {
+    /**
+     * The maximum number of times requests that encounter potentially transient failures should be retried
+     */
     maxRetries?: number;
+    /**
+     * The strategy to retry the request. Using built-in exponential backoff strategy by default.
+     */
     retryStrategy?: RetryStrategy;
   }
   export interface Resolved {