chore(deps): update golang docker tag to v1.26

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [go](https://github.com/actions/go-versions) | uses-with | minor | `1.25` → `1.26` |

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### Release Notes

<details>
<summary>actions/go-versions (go)</summary>

### [`v1.26.0`](https://github.com/actions/go-versions/releases/tag/1.26.0-21889650668): 1.26.0

[Compare Source](https://github.com/actions/go-versions/compare/1.25.7-21696103256...1.26.0-21889650668)

Go 1.26.0

</details>

---

### Configuration

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🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied.

♻ **Rebasing**: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update again.

---

 - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check this box

---

This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
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Reviewed-on: #14
Reviewed-by: Luke Tainton <luke@tainton.uk>
Co-authored-by: renovate[bot] <renovate-bot@git.tainton.uk>
Co-committed-by: renovate[bot] <renovate-bot@git.tainton.uk>

.gitea/workflows/ci.yml

@@ -27,7 +27,7 @@ jobs:
       - name: Setup Go
         uses: actions/setup-go@v6.2.0
         with:
-          go-version: "1.25"
+          go-version: "1.26"
 
       # - name: uv cache
       #   uses: actions/cache@v5

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.25-alpine as build
+FROM golang:1.26-alpine as build
 WORKDIR /go/src/app
 COPY . /go/src/app
 RUN CGO_ENABLED=0 go build -o /go/bin/app