chore(deps): update dependency go to v1.23.6 (hetznercloud/fleeting-plugin-hetzner!214)

This MR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [go](https://go.dev/) ([source](https://github.com/golang/go)) | toolchain | patch | `1.23.5` -> `1.23.6` |

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Author: Hetzner Cloud Bot

go.mod

@@ -2,7 +2,7 @@ module gitlab.com/hetznercloud/fleeting-plugin-hetzner
 
 go 1.22
 
-toolchain go1.23.5
+toolchain go1.23.6
 
 require (
 	github.com/boumenot/gocover-cobertura v1.3.0