rptest: fix S3 bucket deletion

A previous refactor of the code around emptying the bucket and deletion
was buggy. This resulted in tests not cleaning up their buckets
properly. This patch fixes the issue and adds an appropriately scary
error log.

tests/rptest/archival/s3_client.py

@@ -122,8 +122,7 @@ def bucket_is_listable():
             f"Bucket {name} didn't become visible to ListObjectsvv2 requests")
 
     def empty_and_delete_bucket(self, name, parallel=False):
-        failed_deletions = self.cloud_storage_client.empty_bucket(
-            self._si_settings.cloud_storage_bucket, parallel=parallel)
+        failed_deletions = self.empty_bucket(name, parallel=parallel)
 
         assert len(failed_deletions) == 0
         self.delete_bucket(name)

tests/rptest/services/redpanda.py

@@ -2844,7 +2844,15 @@ def add_to_started_nodes(self, node):
     def clean(self, **kwargs):
         super().clean(**kwargs)
         if self.cloud_storage_client:
-            self.delete_bucket_from_si()
+            try:
+                self.delete_bucket_from_si()
+            except Exception as e:
+                self.logger.error(
+                    f"Failed to remove bucket {self._si_settings.cloud_storage_bucket}."
+                    f" This may cause running out of quota in the cloud env. Please investigate: {e}"
+                )
+
+                raise e
 
     def clean_node(self,
                    node,