[cache] Update purge-by-tags.mdx (cloudflare#22750)

Per product's name, Tiered Cache.

Author: nenizera

src/content/docs/cache/how-to/purge-cache/purge-by-tags.mdx

@@ -60,5 +60,5 @@ For information on rate limits, refer to the [Availability and limits](/cache/ho
 
 Purging by tag deletes the resource, resulting in the `CF-Cache-Status` header being set to [`MISS`](/cache/concepts/cache-responses/#miss) for subsequent requests.
 
-If [tiered cache](/cache/how-to/tiered-cache/) is used, purging by tag may return `EXPIRED`, as the lower tier tries to revalidate with the upper tier to reduce load on the latter.
+If [Tiered Cache](/cache/how-to/tiered-cache/) is used, purging by tag may return `EXPIRED`, as the lower tier tries to revalidate with the upper tier to reduce load on the latter.
 Depending on whether the upper tier has the resource or not, and whether the end user is reaching the lower tier or the upper tier, `EXPIRED` or `MISS` are returned.