Bump golang.org/x/oauth2 from 0.5.0 to 0.20.0

Bumps [golang.org/x/oauth2](https://github.com/golang/oauth2) from 0.5.0 to 0.20.0.
- [Commits](golang/oauth2@v0.5.0...v0.20.0)

---
updated-dependencies:
- dependency-name: golang.org/x/oauth2
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

go.mod

@@ -41,7 +41,7 @@ require (
 	go.etcd.io/etcd/client/v3 v3.5.0-alpha.0
 	go.etcd.io/etcd/pkg/v3 v3.5.0-alpha.0
 	golang.org/x/crypto v0.8.0
-	golang.org/x/oauth2 v0.5.0
+	golang.org/x/oauth2 v0.20.0
 	google.golang.org/api v0.40.0
 	google.golang.org/genproto v0.0.0-20210222152913-aa3ee6e6a81c
 	gopkg.in/yaml.v2 v2.4.0

go.sum

@@ -1046,8 +1046,8 @@ golang.org/x/oauth2 v0.0.0-20200902213428-5d25da1a8d43/go.mod h1:KelEdhl1UZF7XfJ
 golang.org/x/oauth2 v0.0.0-20201109201403-9fd604954f58/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/oauth2 v0.0.0-20201208152858-08078c50e5b5/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/oauth2 v0.0.0-20210218202405-ba52d332ba99/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
-golang.org/x/oauth2 v0.5.0 h1:HuArIo48skDwlrvM3sEdHXElYslAMsf3KwRkkW4MC4s=
-golang.org/x/oauth2 v0.5.0/go.mod h1:9/XBHVqLaWO3/BRHs5jbpYCnOZVjj5V0ndyaAM7KB4I=
+golang.org/x/oauth2 v0.20.0 h1:4mQdhULixXKP1rwYBW0vAijoXnkTG0BLCDRzfe1idMo=
+golang.org/x/oauth2 v0.20.0/go.mod h1:XYTD2NtWslqkgxebSiOHnXEap4TF09sJSc7H1sXbhtI=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=