core: Use correct default for connmgr lowWater

Most people weren't affected by this as those values are set in config at init, but for others it would be rather hard to debug.

core/node/groups.go

@@ -41,7 +41,7 @@ func LibP2P(bcfg *BuildCfg, cfg *config.Config) fx.Option {
 	// parse ConnMgr config
 
 	grace := config.DefaultConnMgrGracePeriod
-	low := config.DefaultConnMgrHighWater
+	low := config.DefaultConnMgrLowWater
 	high := config.DefaultConnMgrHighWater
 
 	connmgr := fx.Options()