fix(cdk): changed retry mechanism for hotswapping AppSync.function

packages/aws-cdk/lib/api/hotswap/appsync-mapping-templates.ts

@@ -118,13 +118,13 @@ export async function isHotswappableAppSyncChange(
           const functions = await sdk.appsync().listFunctions({ apiId: sdkRequestObject.apiId });
           const { functionId } = functions.find((fn) => fn.name === physicalName) ?? {};
           // Updating multiple functions at the same time or along with graphql schema results in `ConcurrentModificationException`
-          await simpleRetry(
+          await exponentialBackoffRetry(
             () =>
               sdk.appsync().updateFunction({
                 ...sdkRequestObject,
                 functionId: functionId,
               }),
-            5,
+            1000,
             'ConcurrentModificationException',
           );
         } else if (isGraphQLSchema) {
@@ -169,13 +169,13 @@ async function fetchFileFromS3(s3Url: string, sdk: SDK) {
   return (await sdk.s3().getObject({ Bucket: s3Bucket, Key: s3Key })).Body?.transformToString();
 }
 
-async function simpleRetry(fn: () => Promise<any>, numOfRetries: number, errorCodeToRetry: string) {
+async function exponentialBackoffRetry(fn: () => Promise<any>, backoff: number, errorCodeToRetry: string) {
   try {
     await fn();
   } catch (error: any) {
-    if (error && error.name === errorCodeToRetry && numOfRetries > 0) {
-      await sleep(1000); // wait a whole second
-      await simpleRetry(fn, numOfRetries - 1, errorCodeToRetry);
+    if (error && error.name === errorCodeToRetry) {
+      await sleep(backoff); // time to wait doubles everytime function fails, starts at 1 second
+      await exponentialBackoffRetry(fn, backoff * 2, errorCodeToRetry);
     } else {
       throw error;
     }