Add missing go.sum entry (#1061)

The release failed, complaining about the wrong mousetrap library reference.
This updates it, so we can try releasing again.

Author: kytrinyx

go.sum

@@ -8,6 +8,7 @@ github.com/hashicorp/hcl v0.0.0-20170509225359-392dba7d905e h1:KJWs1uTCkN3E/J5of
 github.com/hashicorp/hcl v0.0.0-20170509225359-392dba7d905e/go.mod h1:oZtUIOe8dh44I2q6ScRibXws4Ajl+d+nod3AaR9vL5w=
 github.com/inconshreveable/go-update v0.0.0-20160112193335-8152e7eb6ccf h1:WfD7VjIE6z8dIvMsI4/s+1qr5EL+zoIGev1BQj1eoJ8=
 github.com/inconshreveable/go-update v0.0.0-20160112193335-8152e7eb6ccf/go.mod h1:hyb9oH7vZsitZCiBt0ZvifOrB+qc8PS5IiilCIb87rg=
+github.com/inconshreveable/mousetrap v1.0.0 h1:Z8tu5sraLXCXIcARxBp/8cbvlwVa7Z1NHg9XEKhtSvM=
 github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANytuPF1OarO4DADm73n8=
 github.com/magiconair/properties v1.7.3 h1:6AOjgCKyZFMG/1yfReDPDz3CJZPxnYk7DGmj2HtyF24=
 github.com/magiconair/properties v1.7.3/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=