fix lmdb mem leak (#640)

go.mod

@@ -3,7 +3,7 @@ module github.com/ledgerwatch/turbo-geth
 go 1.13
 
 require (
-	github.com/AskAlexSharov/lmdb-go v1.8.1-0.20200608080821-6fdb53b47e78
+	github.com/AskAlexSharov/lmdb-go v1.8.1-0.20200609024141-123c53568c38
 	github.com/Azure/azure-storage-blob-go v0.8.0
 	github.com/Azure/go-autorest/autorest/adal v0.8.3 // indirect
 	github.com/JekaMas/notify v0.9.4

go.sum

 cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
-github.com/AskAlexSharov/lmdb-go v1.8.1-0.20200608080821-6fdb53b47e78 h1:oHoQ7THIToKhelqoWL296YCGV8yogP4KtQQuqfPMKO4=
-github.com/AskAlexSharov/lmdb-go v1.8.1-0.20200608080821-6fdb53b47e78/go.mod h1:k7Jo/kN60Hq1MTBwsVSp2JllEs5Tyhd4MZ7tY9smjeA=
+github.com/AskAlexSharov/lmdb-go v1.8.1-0.20200609024141-123c53568c38 h1:0lvFLmXBPIKQSwbMBc6CC+v93gqWn/wiwmlEs1/EURE=
+github.com/AskAlexSharov/lmdb-go v1.8.1-0.20200609024141-123c53568c38/go.mod h1:k7Jo/kN60Hq1MTBwsVSp2JllEs5Tyhd4MZ7tY9smjeA=
 github.com/Azure/azure-pipeline-go v0.2.1 h1:OLBdZJ3yvOn2MezlWvbrBMTEUQC72zAftRZOMdj5HYo=
 github.com/Azure/azure-pipeline-go v0.2.1/go.mod h1:UGSo8XybXnIGZ3epmeBw7Jdz+HiUVpqIlpz/HKHylF4=
 github.com/Azure/azure-storage-blob-go v0.8.0 h1:53qhf0Oxa0nOjgbDeeYPUeyiNmafAFEY95rZLK0Tj6o=