Bump github.com/prometheus/common from 0.19.0 to 0.20.0 (#17)

Bumps [github.com/prometheus/common](https://github.com/prometheus/common) from 0.19.0 to 0.20.0.
- [Release notes](https://github.com/prometheus/common/releases)
- [Commits](prometheus/common@v0.19.0...v0.20.0)

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

go.mod

@@ -4,6 +4,6 @@ go 1.12
 
 require (
 	github.com/prometheus/client_golang v1.10.0
-	github.com/prometheus/common v0.19.0
+	github.com/prometheus/common v0.20.0
 	gopkg.in/alecthomas/kingpin.v2 v2.2.6
 )

go.sum

@@ -227,8 +227,8 @@ github.com/prometheus/common v0.4.1/go.mod h1:TNfzLD0ON7rHzMJeJkieUDPYmFC7Snx/y8
 github.com/prometheus/common v0.7.0/go.mod h1:DjGbpBbp5NYNiECxcL/VnbXCCaQpKd3tt26CguLLsqA=
 github.com/prometheus/common v0.10.0/go.mod h1:Tlit/dnDKsSWFlCLTWaA1cyBgKHSMdTB80sz/V91rCo=
 github.com/prometheus/common v0.18.0/go.mod h1:U+gB1OBLb1lF3O42bTCL+FK18tX9Oar16Clt/msog/s=
-github.com/prometheus/common v0.19.0 h1:Itb4+NjG9wRdkAWgVucbM/adyIXxEhbw0866e0uZE6A=
-github.com/prometheus/common v0.19.0/go.mod h1:U+gB1OBLb1lF3O42bTCL+FK18tX9Oar16Clt/msog/s=
+github.com/prometheus/common v0.20.0 h1:pfeDeUdQcIxOMutNjCejsEFp7qeP+/iltHSSmLpE+hU=
+github.com/prometheus/common v0.20.0/go.mod h1:U+gB1OBLb1lF3O42bTCL+FK18tX9Oar16Clt/msog/s=
 github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/prometheus/procfs v0.0.0-20190117184657-bf6a532e95b1/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/prometheus/procfs v0.0.2/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=