Update Go Deps

Change-Id: Ia1e7600b131dda99dae15a35cf50f949d4aeb7ee
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/265266
Reviewed-by: <skia-recreate-skps@skia-swarming-bots.iam.gserviceaccount.com>
Commit-Queue: <skia-recreate-skps@skia-swarming-bots.iam.gserviceaccount.com>
diff --git a/go.mod b/go.mod
index a82bb98..a2fcc47 100644
--- a/go.mod
+++ b/go.mod
@@ -63,6 +63,7 @@
 	github.com/patrickmn/go-cache v2.1.0+incompatible
 	github.com/pmezard/go-difflib v1.0.0
 	github.com/prometheus/client_golang v1.3.0
+	github.com/prometheus/client_model v0.2.0 // indirect
 	github.com/prometheus/common v0.8.0 // indirect
 	github.com/robertkrimen/otto v0.0.0-20180617131154-15f95af6e78d // indirect
 	github.com/rogpeppe/go-internal v1.5.0 // indirect
diff --git a/go.sum b/go.sum
index 5c6af15..5905d50 100644
--- a/go.sum
+++ b/go.sum
@@ -377,6 +377,8 @@
 github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
 github.com/prometheus/client_model v0.1.0 h1:ElTg5tNp4DqfV7UQjDqv2+RJlNzsDtvNAWccbItceIE=
 github.com/prometheus/client_model v0.1.0/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
+github.com/prometheus/client_model v0.2.0 h1:uq5h0d+GuxiXLJLNABMgp2qUWDPiLvgCzz2dUR+/W/M=
+github.com/prometheus/client_model v0.2.0/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
 github.com/prometheus/common v0.4.1 h1:K0MGApIoQvMw27RTdJkPbr3JZ7DNbtxQNyi5STVM6Kw=
 github.com/prometheus/common v0.4.1/go.mod h1:TNfzLD0ON7rHzMJeJkieUDPYmFC7Snx/y86RQel1bk4=
 github.com/prometheus/common v0.6.0 h1:kRhiuYSXR3+uv2IbVbZhUxK5zVD/2pp3Gd2PpvPkpEo=