Update actions/checkout action to v5 (#237)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://redirect.github.com/actions/checkout) |
action | major | `v4` -> `v5` |

---

### Release Notes

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

### [`v5`](https://redirect.github.com/actions/checkout/compare/v4...v5)

[Compare
Source](https://redirect.github.com/actions/checkout/compare/v4...v5)

</details>

---

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---

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---

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.github/workflows/deploy.yml

@@ -11,7 +11,7 @@ jobs:
     if: github.event_name != 'push'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - uses: actions/setup-node@v5
         with:
           node-version: 22
@@ -24,7 +24,7 @@ jobs:
     if: github.event_name != 'pull_request'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - uses: actions/setup-node@v5
         with:
           node-version: 22

.github/workflows/pr-checks.yml

@@ -7,7 +7,7 @@ jobs:
   pr-checks:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - uses: actions/setup-node@v5
         with:
           cache: "yarn"