chore(deps): update actions/checkout action to v6.0.3 (#2175)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://redirect.github.com/actions/checkout) |
action | patch | `v6.0.2` → `v6.0.3` |

---

### Release Notes

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

###
[`v6.0.3`](https://redirect.github.com/actions/checkout/blob/HEAD/CHANGELOG.md#v603)

[Compare
Source](https://redirect.github.com/actions/checkout/compare/v6.0.2...v6.0.3)

- Fix checkout init for SHA-256 repositories by
[@&#8203;yaananth](https://redirect.github.com/yaananth) in
[#&#8203;2439](https://redirect.github.com/actions/checkout/pull/2439)
- fix: expand merge commit SHA regex and add SHA-256 test cases by
[@&#8203;yaananth](https://redirect.github.com/yaananth) in
[#&#8203;2414](https://redirect.github.com/actions/checkout/pull/2414)

</details>

---

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---

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.github/workflows/java-version-matrix-tests.yml

@@ -26,7 +26,7 @@ jobs:
         java-version: [8, 11, 17, 21, 25]
     steps:
       - name: Check out
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
         with:
           persist-credentials: false
 

.github/workflows/lint.yml

@@ -15,7 +15,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
         with:
           persist-credentials: false
           fetch-depth: 0 # needed for git diff --merge-base in lint:links

.github/workflows/nightly-benchmarks.yml

@@ -28,7 +28,7 @@ jobs:
       contents: read # checkout only
     steps:
       - name: Checkout main branch
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
         with:
           persist-credentials: false
           fetch-depth: 0
@@ -75,7 +75,7 @@ jobs:
       contents: write # push generated results to the benchmarks branch
     steps:
       - name: Checkout
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
         with:
           # zizmor: ignore[artipacked] -- needs credentials to push to benchmarks branch
           persist-credentials: true