implement and use striped LRU cache to lower mutex contention (#15764)

* Implement Striped LRU cache

* ci

* fix

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

app/post_metadata.go

@@ -31,7 +31,7 @@ const LINK_CACHE_SIZE = 10000
 const LINK_CACHE_DURATION = 1 * time.Hour
 const MaxMetadataImageSize = MaxOpenGraphResponseSize
 
-var linkCache = cache.NewLRU(&cache.LRUOptions{
+var linkCache = cache.NewLRU(cache.LRUOptions{
 	Size: LINK_CACHE_SIZE,
 })