chore(deps): update actions/checkout action to v6 (#4757)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://redirect.github.com/actions/checkout) |
action | major | `v5.0.1` -> `v6.0.0` |

---

### Release Notes

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

###
[`v6.0.0`](https://redirect.github.com/actions/checkout/compare/v5.0.1...v6.0.0)

[Compare
Source](https://redirect.github.com/actions/checkout/compare/v5.0.1...v6.0.0)

</details>

---

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Automerge - At any time (no schedule defined).

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are satisfied.

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rebase/retry checkbox.

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

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---

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.github/workflows/checks.yaml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: check out code
-      uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
     - name: install dependencies
       run: npm install
@@ -27,7 +27,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: check out code
-      uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
     - uses: actions/setup-python@e797f83bcb11b83ae66e0230d6156d7c80228e7c # v6.0.0
 
@@ -41,7 +41,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: check out code
-      uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
     - name: install dependencies
       run: npm install
@@ -56,7 +56,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: check out code
-      uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
     - name: install dependencies
       run: npm install
@@ -71,7 +71,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: check out code
-      uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
     - name: run compliance-matrix
       run: make compliance-matrix
@@ -83,7 +83,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: check out code
-      uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
     - name: run misspell
       run: make misspell

.github/workflows/fossa.yml

@@ -12,7 +12,7 @@ jobs:
   fossa:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
       - uses: fossas/fossa-action@3ebcea1862c6ffbd5cf1b4d0bd6b3fe7bd6f2cac # v1.7.0
         with:

.github/workflows/ossf-scorecard.yml

@@ -19,7 +19,7 @@ jobs:
       # Needed for GitHub OIDC token if publish_results is true
       id-token: write
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
         with:
           persist-credentials: false
 

.github/workflows/triage-followup.yml

@@ -17,7 +17,7 @@ jobs:
       run:
         working-directory: ./.github/scripts/triage-helper
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - uses: actions/setup-python@e797f83bcb11b83ae66e0230d6156d7c80228e7c # v6.0.0
         with:
           python-version: 3.14