chore(deps): Update dependency go to v1.21.0 (#14277)

This PR contains the following updates:

| Package | Type | Update | Change | Pending |
|---|---|---|---|---|
| [go](https://go.dev/) ([source](https://togithub.com/golang/go)) |  | minor | `1.20.5` -> `1.21.0` | `1.21.1` |
| [go](https://go.dev/) ([source](https://togithub.com/golang/go)) | golang | minor | `1.20` -> `1.21` | `1.21.1` |

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