Removed indices.flushSynced from API reference

- Fix for https://github.com/elastic/elasticsearch/pull/50882

docs/reference.asciidoc

@@ -2595,35 +2595,6 @@ _Default:_ `open`
 
 |===
 
-=== indices.flushSynced
-
-[source,ts]
-----
-client.indices.flushSynced({
-  index: string | string[],
-  ignore_unavailable: boolean,
-  allow_no_indices: boolean,
-  expand_wildcards: 'open' | 'closed' | 'none' | 'all'
-})
-----
-link:{ref}/indices-synced-flush-api.html[Reference]
-[cols=2*]
-|===
-|`index`
-|`string \| string[]` - A comma-separated list of index names; use `_all` or empty string for all indices
-
-|`ignore_unavailable` or `ignoreUnavailable`
-|`boolean` - Whether specified concrete indices should be ignored when unavailable (missing or closed)
-
-|`allow_no_indices` or `allowNoIndices`
-|`boolean` - Whether to ignore if a wildcard indices expression resolves into no concrete indices. (This includes `_all` string or when no indices have been specified)
-
-|`expand_wildcards` or `expandWildcards`
-|`'open' \| 'closed' \| 'none' \| 'all'` - Whether to expand wildcard expression to concrete indices that are open, closed or both. +
-_Default:_ `open`
-
-|===
-
 === indices.forcemerge
 
 [source,ts]