refactor: tighter variable scoping

note that without the type def it falls back to 'any'

'response' implicitly has type 'any' because it does not have a type annotation and is referenced directly or indirectly in its own initializer.ts(7022)

packages/aws-cdk/lib/api/evaluate-cloudformation-template.ts

@@ -67,9 +67,8 @@ export class LazyLookupExport implements LookupExport {
 
   private async * listExports() {
     let nextToken: string | undefined = undefined;
-    let response: PromiseResult<AWS.CloudFormation.ListExportsOutput, AWS.AWSError>;
     while (true) {
-      response = await this.sdk.cloudFormation().listExports({
+      const response: PromiseResult<AWS.CloudFormation.ListExportsOutput, AWS.AWSError> = await this.sdk.cloudFormation().listExports({
         NextToken: nextToken,
       }).promise();