fix(deps): update module golang.org/x/oauth2 to v0.21.0 (#39)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| golang.org/x/oauth2 | `v0.20.0` -> `v0.21.0` |
[![age](https://developer.mend.io/api/mc/badges/age/go/golang.org%2fx%2foauth2/v0.21.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
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|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/go/golang.org%2fx%2foauth2/v0.20.0/v0.21.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
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go.mod

@@ -8,7 +8,7 @@ require (
 	github.com/charmbracelet/log v0.4.0
 	github.com/minchao/go-apple-music v0.0.0-20230815040201-3b2aec2d7ffe
 	github.com/zmb3/spotify/v2 v2.4.2
-	golang.org/x/oauth2 v0.20.0
+	golang.org/x/oauth2 v0.21.0
 	golang.org/x/term v0.21.0
 	mvdan.cc/xurls/v2 v2.5.0
 )

go.sum

@@ -252,6 +252,8 @@ golang.org/x/oauth2 v0.0.0-20200107190931-bf48bf16ab8d/go.mod h1:gOpvHmFTYa4Iltr
 golang.org/x/oauth2 v0.0.0-20210810183815-faf39c7919d5/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/oauth2 v0.20.0 h1:4mQdhULixXKP1rwYBW0vAijoXnkTG0BLCDRzfe1idMo=
 golang.org/x/oauth2 v0.20.0/go.mod h1:XYTD2NtWslqkgxebSiOHnXEap4TF09sJSc7H1sXbhtI=
+golang.org/x/oauth2 v0.21.0 h1:tsimM75w1tF/uws5rbeHzIWxEqElMehnc+iW793zsZs=
+golang.org/x/oauth2 v0.21.0/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=