tapcfg: Update root-node-page-cache-size default value

Author: itsrachelfish

sample-tapd.conf

@@ -328,8 +328,8 @@
 ; universe.multiverse-caches.syncer-cache-pre-alloc-size=100000
 
 ; The size of the root node page cache for all requests that aren't served by
-; the syncer cache. (default: 10240)
-; universe.multiverse-caches.root-node-page-cache-size=10240
+; the syncer cache. (default: 327680)
+; universe.multiverse-caches.root-node-page-cache-size=327680
 
 
 [address]