Update https://gitea.seeseepuff.be/actions/watchtower action to v2 (#9)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [https://gitea.seeseepuff.be/actions/watchtower](https://gitea.seeseepuff.be/actions/watchtower) | action | major | `v1` → `v2` |

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### Release Notes

<details>
<summary>actions/watchtower (https://gitea.seeseepuff.be/actions/watchtower)</summary>

### [`v2`](https://gitea.seeseepuff.be/actions/watchtower/compare/v1...v2)

[Compare Source](https://gitea.seeseepuff.be/actions/watchtower/compare/v1...v2)

</details>

---

### Configuration

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  - At any time (no schedule defined)
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♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

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

---

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This PR has been generated by [Mend Renovate](https://github.com/renovatebot/renovate).
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Reviewed-on: #9
Co-authored-by: Renovate Bot <sebastiaan.de.schaetzen+renovate@gmail.com>
Co-committed-by: Renovate Bot <sebastiaan.de.schaetzen+renovate@gmail.com>

.gitea/workflows/build.yml

@@ -9,10 +9,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v6
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
 
       - name: Setup Java
-        uses: actions/setup-java@v5
+        uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654 # v5
         with:
           distribution: 'temurin'
           java-version: '25'

.gitea/workflows/deploy.yml

@@ -8,10 +8,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v6
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
 
       - name: Setup Java
-        uses: actions/setup-java@v5
+        uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654 # v5
         with:
           distribution: 'temurin'
           java-version: '25'
@@ -35,4 +35,4 @@ jobs:
         run: docker push gitea.seeseepuff.be/seeseemelk/webgit:latest
 
       - name: Trigger Watchtower
-        uses: https://gitea.seeseepuff.be/actions/watchtower@v1
+        uses: https://gitea.seeseepuff.be/actions/watchtower@2bf31c49a6f57d45a1580c7004911afb714fb188 # v2

Dockerfile

@@ -1,4 +1,4 @@
-FROM eclipse-temurin:25-alpine
+FROM eclipse-temurin:25-alpine@sha256:30d9f87d702c2c1c601ed0d31e0c88ea1ea474ee7676cda7b7a59e759181c4dd
 WORKDIR /app
 ADD ./build/libs/webgit-0.0.1-SNAPSHOT.jar /app/webgit.jar
 ENTRYPOINT ["java", "-jar", "webgit.jar"]