Update firefly-common snapshot

Signed-off-by: Andrew Richardson <andrew.richardson@kaleido.io>

go.mod

@@ -13,7 +13,7 @@ require (
 	github.com/golang-migrate/migrate/v4 v4.15.2
 	github.com/gorilla/mux v1.8.0
 	github.com/gorilla/websocket v1.5.0
-	github.com/hyperledger/firefly-common v0.1.16
+	github.com/hyperledger/firefly-common v0.1.20
 	github.com/hyperledger/firefly-signer v0.9.12
 	github.com/jarcoal/httpmock v1.1.0
 	github.com/karlseguin/ccache v2.0.3+incompatible

go.sum

@@ -727,8 +727,10 @@ github.com/hashicorp/serf v0.9.6/go.mod h1:TXZNMjZQijwlDvp+r0b63xZ45H7JmCmgg4gpT
 github.com/hashicorp/serf v0.9.7/go.mod h1:TXZNMjZQijwlDvp+r0b63xZ45H7JmCmgg4gpTwn9UV4=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/hyperledger/firefly-common v0.1.13/go.mod h1:2NqPi5Ud9H6rSlZXkLbotxW7z4EAD89p3/8oNOpm9Gs=
-github.com/hyperledger/firefly-common v0.1.16 h1:21xidDEKrJhtGdBSRqHN4PfDi7aYxF0HOFuAa04V1AE=
-github.com/hyperledger/firefly-common v0.1.16/go.mod h1:MNbaI2spBsdZYOub6Duj9xueE7Qyu9itOmJ4vE8tjYw=
+github.com/hyperledger/firefly-common v0.1.19 h1:fGZiWMCysG9AVFcEeOoajBifroerET/o0yYc4sfm6VA=
+github.com/hyperledger/firefly-common v0.1.19/go.mod h1:gMlv4Iy5JjnzXmSEdb+tWVDIc/2GhL9MRcgNX+VmI4M=
+github.com/hyperledger/firefly-common v0.1.20 h1:0dShkjlIShyBxkXRmu3vLmpEK6xrqmfc8GhF6k0Vgbg=
+github.com/hyperledger/firefly-common v0.1.20/go.mod h1:gMlv4Iy5JjnzXmSEdb+tWVDIc/2GhL9MRcgNX+VmI4M=
 github.com/hyperledger/firefly-signer v0.9.12 h1:pCPiGHx1+MbTsIQuRkoQmfWxvpcvtGHVavls0NnH0po=
 github.com/hyperledger/firefly-signer v0.9.12/go.mod h1:GPQRUZOFOAjkLmg8GDjZUjEdUD0gcar+CSVhwltIwyw=
 github.com/iancoleman/strcase v0.2.0/go.mod h1:iwCmte+B7n89clKwxIoIXy/HfoL7AsD47ZCWhYzw7ho=