chore(deps): update dependency go to v1.23.4 (#691)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [go](https://go.dev/) ([source](https://github.com/golang/go)) | toolchain | patch | `1.23.3` -> `1.23.4` |

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Reviewed-on: https://gitea.com/gitea/tea/pulls/691
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: Renovate Bot <renovate-bot@gitea.com>
Co-committed-by: Renovate Bot <renovate-bot@gitea.com>

go.mod

@@ -2,7 +2,7 @@ module code.gitea.io/tea
 
 go 1.21
 
-toolchain go1.23.3
+toolchain go1.23.4
 
 require (
 	code.gitea.io/gitea-vet v0.2.3