chore(cli): more accurate message to garbage collection prompt (#32178)

Should look like this:

```
Found 1 image to delete based off of the following criteria:
- images have been isolated for > 0 days
- images were created > 0 days ago

Delete this batch (yes/no/delete-all)? 
```

Instead of this:

```
Found 1 assets to delete based off of the following criteria:
- assets have been isolated for > 0 days
- assets were created > 0 days ago

Delete this batch (yes/no/delete-all)? 
```

----

*By submitting this pull request, I confirm that my contribution is made
under the terms of the Apache-2.0 license*

---------

Co-authored-by: Momo Kornher <[email protected]>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Author: 3 people

packages/aws-cdk/lib/api/garbage-collection/garbage-collector.ts

@@ -284,7 +284,7 @@ export class GarbageCollector {
         debug(`${untaggables.length} assets to untag`);
 
         if (this.permissionToDelete && deletables.length > 0) {
-          await this.confirmationPrompt(printer, deletables);
+          await this.confirmationPrompt(printer, deletables, 'image');
           await this.parallelDeleteEcr(ecr, repo, deletables, printer);
         }
 
@@ -360,7 +360,7 @@ export class GarbageCollector {
         debug(`${untaggables.length} assets to untag`);
 
         if (this.permissionToDelete && deletables.length > 0) {
-          await this.confirmationPrompt(printer, deletables);
+          await this.confirmationPrompt(printer, deletables, 'object');
           await this.parallelDeleteS3(s3, bucket, deletables, printer);
         }
 
@@ -713,12 +713,16 @@ export class GarbageCollector {
     } while (continuationToken);
   }
 
-  private async confirmationPrompt(printer: ProgressPrinter, deletables: GcAsset[]) {
+  private async confirmationPrompt(printer: ProgressPrinter, deletables: GcAsset[], type: string) {
+    const pluralize = (name: string, count: number): string => {
+      return count === 1 ? name : `${name}s`;
+    };
+
     if (this.confirm) {
       const message = [
-        `Found ${deletables.length} assets to delete based off of the following criteria:`,
-        `- assets have been isolated for > ${this.props.rollbackBufferDays} days`,
-        `- assets were created > ${this.props.createdBufferDays} days ago`,
+        `Found ${deletables.length} ${pluralize(type, deletables.length)} to delete based off of the following criteria:`,
+        `- ${type}s have been isolated for > ${this.props.rollbackBufferDays} days`,
+        `- ${type}s were created > ${this.props.createdBufferDays} days ago`,
         '',
         'Delete this batch (yes/no/delete-all)?',
       ].join('\n');