update metric endpoints

Author: james-laing

specification/metrics/purefb-metrics.md

@@ -27,9 +27,9 @@ This document describes the semantic conventions for Pure FlashBlade Metrics.
 | -------------------- | ------------------------ | ----------------------------------------------------------------- |
 | /metrics             | Full array metrics       | all                                                               |
 | /metrics/array       | Array only metrics       | `purefb_info`, `purefb_alerts`, `purefb_array`, `purefb_hardware` |
-| /metrics/buckets     | Bucket only metrics      | `purefb_info`, `purefb_buckets`, `purefb_object_store`            |
+| /metrics/objectstore | Object Store metrics     | `purefb_info`, `purefb_buckets`, `purefb_object_store`            |
 | /metrics/clients     | Client only metrics      | `purefb_info`, `purefb_clients`                                   |
-| /metrics/filesystems | File System only metrics | `purefb_info`, `purefb_file_systems`                              |
+| /metrics/filesystems | File System metrics      | `purefb_info`, `purefb_file_systems`                              |
 | /metrics/usage       | Quota only metrics       | `purefb_info`, `purefb_file_system_usage`                         |
 | /metrics/policies    | NFS policy related info  | `purefb_info`, `purefb_nfs_export_rule`                           |