chore(deps): update dawidd6/action-send-mail action to v4 (#40)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [dawidd6/action-send-mail](https://github.com/dawidd6/action-send-mail) | action | major | `v3` -> `v4` |

---

### Release Notes

<details>
<summary>dawidd6/action-send-mail (dawidd6/action-send-mail)</summary>

### [`v4`](https://github.com/dawidd6/action-send-mail/releases/tag/v4)

[Compare Source](https://github.com/dawidd6/action-send-mail/compare/v3...v4)

##### What's Changed

-   build(deps): bump nodemailer from 6.9.13 to 6.9.14 by [@&#8203;dependabot](https://github.com/dependabot) in https://github.com/dawidd6/action-send-mail/pull/206
-   build(deps): bump nodemailer from 6.9.14 to 6.9.15 by [@&#8203;dependabot](https://github.com/dependabot) in https://github.com/dawidd6/action-send-mail/pull/212
-   build(deps): bump [@&#8203;actions/core](https://github.com/actions/core) from 1.10.1 to 1.11.0 by [@&#8203;dependabot](https://github.com/dependabot) in https://github.com/dawidd6/action-send-mail/pull/216
-   build(deps): bump [@&#8203;actions/core](https://github.com/actions/core) from 1.11.0 to 1.11.1 by [@&#8203;dependabot](https://github.com/dependabot) in https://github.com/dawidd6/action-send-mail/pull/217
-   build(deps): bump nodemailer from 6.9.15 to 6.9.16 by [@&#8203;dependabot](https://github.com/dependabot) in https://github.com/dawidd6/action-send-mail/pull/218
-   Enable the Showdown option to support tables by [@&#8203;phoeniixhawk](https://github.com/phoeniixhawk) in https://github.com/dawidd6/action-send-mail/pull/220

**Full Changelog**: https://github.com/dawidd6/action-send-mail/compare/v3.12.0...v4

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 **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).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiIzOS4yMC42IiwidXBkYXRlZEluVmVyIjoiMzkuMjAuNiIsInRhcmdldEJyYW5jaCI6Im1hc3RlciIsImxhYmVscyI6W119-->

Reviewed-on: #40
Co-authored-by: Renovate Bot <renovate@mgrote.net>
Co-committed-by: Renovate Bot <renovate@mgrote.net>

.gitea/workflows/build.yaml

@@ -26,7 +26,7 @@ jobs:
 #        with:
 #          cli-args: "shell.sh"
       - name: Send notification
-        uses: dawidd6/action-send-mail@v3
+        uses: dawidd6/action-send-mail@v4
         if: failure()
         with:
           connection_url: smtp://docker10.mgrote.net:1025
@@ -75,7 +75,7 @@ jobs:
           push: true
           tags: ${{ steps.meta.outputs.tags }}
       - name: Send notification
-        uses: dawidd6/action-send-mail@v3
+        uses: dawidd6/action-send-mail@v4
         if: failure()
         with:
           connection_url: smtp://docker10.mgrote.net:1025