kernel-builder: fix failed uploads trying to remove directories (#516)

When trying to collect candidates for stale entries, we included
directories as well. This causes upload failures, since directories
are not Git objects and the API would reject these.

Author: danieldk

kernel-builder/src/upload.rs

@@ -188,9 +188,9 @@ fn run_upload_typed<T: RepoType>(args: UploadArgs) -> Result<()> {
             .send()
             .unwrap_or_default()
             .into_iter()
-            .map(|entry| match entry {
-                hf_hub::repository::RepoTreeEntry::File { path, .. } => path,
-                hf_hub::repository::RepoTreeEntry::Directory { path, .. } => path,
+            .filter_map(|entry| match entry {
+                hf_hub::repository::RepoTreeEntry::File { path, .. } => Some(path),
+                hf_hub::repository::RepoTreeEntry::Directory { .. } => None,
             })
             .collect();