backend-common: end write stream after use in ZipArchiveResponse

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

.changeset/great-walls-brake.md

@@ -0,0 +1,5 @@
+---
+'@backstage/backend-common': patch
+---
+
+Properly close write stream when writing temporary archive for processing zip-based `.readTree()` responses.

packages/backend-common/src/reading/tree/ZipArchiveResponse.ts

@@ -93,12 +93,13 @@ export class ZipArchiveResponse implements ReadTreeResponse {
 
     return new Promise((resolve, reject) => {
       writeStream.on('error', reject);
-      writeStream.on('finish', () =>
+      writeStream.on('finish', () => {
+        writeStream.end();
         resolve({
           fileName: tmpFile,
           cleanup: () => fs.rm(tmpDir, { recursive: true }),
-        }),
-      );
+        });
+      });
       stream.pipe(writeStream);
     });
   }