Fix ephemeral file warning on secondaries (#7201)

A test was added which exercises secondary locations more, and there was
a location in the secondary downloader that warned on ephemeral files.

This was intended to be fixed in this faulty commit:
8cea866adf

pageserver/src/tenant/secondary/downloader.rs

@@ -11,11 +11,11 @@ use crate::{
     disk_usage_eviction_task::{
         finite_f32, DiskUsageEvictionInfo, EvictionCandidate, EvictionLayer, EvictionSecondaryLayer,
     },
-    is_temporary,
     metrics::SECONDARY_MODE,
     tenant::{
         config::SecondaryLocationConfig,
         debug_assert_current_span_has_tenant_and_timeline_id,
+        ephemeral_file::is_ephemeral_file,
         remote_timeline_client::{
             index::LayerFileMetadata, is_temp_download_file, FAILED_DOWNLOAD_WARN_THRESHOLD,
             FAILED_REMOTE_OP_RETRIES,
@@ -964,7 +964,7 @@ async fn init_timeline_state(
             continue;
         } else if crate::is_temporary(&file_path)
             || is_temp_download_file(&file_path)
-            || is_temporary(&file_path)
+            || is_ephemeral_file(file_name)
         {
             // Temporary files are frequently left behind from restarting during downloads
             tracing::info!("Cleaning up temporary file {file_path}");

test_runner/regress/test_pageserver_metric_collection.py

@@ -70,6 +70,7 @@ def test_metric_collection(
             # we have a fast rate of calculation, these can happen at shutdown
             ".*synthetic_size_worker:calculate_synthetic_size.*:gather_size_inputs.*: failed to calculate logical size at .*: cancelled.*",
             ".*synthetic_size_worker: failed to calculate synthetic size for tenant .*: failed to calculate some logical_sizes",
+            ".*metrics_collection: failed to upload to S3: Failed to upload data of length .* to storage path.*",
         ]
     )