chore(deps): Update actions/checkout action to v5 (#118)

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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.github/workflows/ci-go-load-tests.yaml

@@ -21,7 +21,7 @@ jobs:
     runs-on: warp-ubuntu-latest-arm64-4x
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
 
       - name: Set up Go
         uses: actions/setup-go@v5

.github/workflows/ci-go-unit-tests.yaml

@@ -32,7 +32,7 @@ jobs:
         os: [linux, macos]
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
 
       - name: Set up Go
         uses: actions/setup-go@v5