chore(deps): update gradle/actions action to v4 (#324)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [gradle/actions](https://redirect.github.com/gradle/actions) | action
| major | `v3` -> `v4` |

---

### Release Notes

<details>
<summary>gradle/actions (gradle/actions)</summary>

### [`v4`](https://redirect.github.com/gradle/actions/compare/v3...v4)

[Compare
Source](https://redirect.github.com/gradle/actions/compare/v3...v4)

</details>

---

### Configuration

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Automerge - At any time (no schedule defined).

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

♻ **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.

---

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

---

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.github/workflows/gh-pages.yml

@@ -30,7 +30,7 @@ jobs:
         run: npm ci --prefer-offline --no-audit
 
       - name: Set up Gradle
-        uses: gradle/actions/setup-gradle@v3
+        uses: gradle/actions/setup-gradle@v4
 
       - name: Gradle build
         run: ./gradlew build

.github/workflows/pull_request.yml

@@ -31,7 +31,7 @@ jobs:
         run: npm ci --prefer-offline --no-audit
 
       - name: Set up Gradle
-        uses: gradle/actions/setup-gradle@v3
+        uses: gradle/actions/setup-gradle@v4
 
       - name: Gradle build
         run: ./gradlew build