fix(deps): update module github.com/spf13/cobra to v1.2.1 (#785)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [github.com/spf13/cobra](https://togithub.com/spf13/cobra) | require | patch | `v1.2.0` -> `v1.2.1` |

---

### Release Notes

<details>
<summary>spf13/cobra</summary>

### [`v1.2.1`](https://togithub.com/spf13/cobra/releases/v1.2.1)

[Compare Source](https://togithub.com/spf13/cobra/compare/v1.2.0...v1.2.1)

##### Bug fixes

-   Quickfix for spf13/cobra#1437 after v1.2.0 where parallel use of the `cmd.RegisterFlagCompletionFunc()` (and subsequent map) now works correctly and flag completions now work again

</details>

---

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---

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go.mod

@@ -9,7 +9,7 @@ require (
 	github.com/gorilla/mux v1.8.0
 	github.com/iancoleman/strcase v0.1.3
 	github.com/soheilhy/cmux v0.1.5
-	github.com/spf13/cobra v1.2.0
+	github.com/spf13/cobra v1.2.1
 	github.com/spf13/viper v1.8.1
 	golang.org/x/oauth2 v0.0.0-20210628180205-a41e5a781914
 	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c

go.sum

@@ -241,8 +241,8 @@ github.com/spf13/afero v1.6.0 h1:xoax2sJ2DT8S8xA2paPFjDCScCNeWsg75VG0DLRreiY=
 github.com/spf13/afero v1.6.0/go.mod h1:Ai8FlHk4v/PARR026UzYexafAt9roJ7LcLMAmO6Z93I=
 github.com/spf13/cast v1.3.1 h1:nFm6S0SMdyzrzcmThSipiEubIDy8WEXKNZ0UOgiRpng=
 github.com/spf13/cast v1.3.1/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
-github.com/spf13/cobra v1.2.0 h1:IHGo93KUJjih0Gz449MCBDKuaWPqcKcbuUM7GXWFnlw=
-github.com/spf13/cobra v1.2.0/go.mod h1:ExllRjgxM/piMAM+3tAZvg8fsklGAf3tPfi+i8t68Nk=
+github.com/spf13/cobra v1.2.1 h1:+KmjbUw1hriSNMF55oPrkZcb27aECyrj8V2ytv7kWDw=
+github.com/spf13/cobra v1.2.1/go.mod h1:ExllRjgxM/piMAM+3tAZvg8fsklGAf3tPfi+i8t68Nk=
 github.com/spf13/jwalterweatherman v1.1.0 h1:ue6voC5bR5F8YxI5S67j9i582FU4Qvo2bmqnqMYADFk=
 github.com/spf13/jwalterweatherman v1.1.0/go.mod h1:aNWZUN0dPAAO/Ljvb5BEdw96iTZ0EXowPYD95IqWIGo=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=