Remove option to retain vectors from ILiveTableTx openWatermark

There should be no need to retain the vectors backing the Live Table
during a transaction as said transaction is the only thing able to mutate
the Live Table.

core/src/main/clojure/xtdb/indexer/live_index.clj

@@ -27,7 +27,7 @@
 
 #_{:clj-kondo/ignore [:clojure-lsp/unused-public-var]}
 (definterface ILiveTableTx
- (^xtdb.indexer.live_index.ILiveTableWatermark openWatermark [^boolean retain])
+ (^xtdb.indexer.live_index.ILiveTableWatermark openWatermark [])
  (^xtdb.vector.IVectorWriter docWriter [])
  (^void logPut [^java.nio.ByteBuffer iid, ^long validFrom, ^long validTo, writeDocFn])
  (^void logDelete [^java.nio.ByteBuffer iid, ^long validFrom, ^long validTo])
@@ -141,9 +141,9 @@
 
  (swap! !transient-trie #(.add ^LiveHashTrie % (dec (.getPosition (.writerPosition live-rel))))))
 
- (openWatermark [_ retain?]
+ (openWatermark [_]
  (locking this-table
- (let [wm-live-rel (open-wm-live-rel live-rel retain?)
+ (let [wm-live-rel (open-wm-live-rel live-rel false)
  col-types (live-rel->col-types wm-live-rel)
  wm-live-trie @!transient-trie]
 
@@ -153,8 +153,7 @@
  (liveTrie [_] wm-live-trie)
 
  AutoCloseable
- (close [_]
- (when retain? (util/close wm-live-rel)))))))
+ (close [_])))))
 
  (commit [_]
  (locking this-table
@@ -252,7 +251,7 @@
  (openWatermark [_]
  (util/with-close-on-catch [wms (HashMap.)]
  (doseq [[table-name ^ILiveTableTx live-table] table-txs]
- (.put wms table-name (.openWatermark live-table false)))
+ (.put wms table-name (.openWatermark live-table)))
 
  (doseq [[table-name ^ILiveTable live-table] tables]
  (.computeIfAbsent wms table-name