Update actions/checkout digest to 8ade135 (#5)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://togithub.com/actions/checkout) | action |
digest | `3df4ab1` -> `8ade135` |

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.github/workflows/deploy.yml

@@ -7,7 +7,7 @@ jobs:
         runs-on: ubuntu-latest
         steps:
             - name: checkout source
-              uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
+              uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # v4
 
             - name: Run chktex
               uses: xu-cheng/texlive-action/full@v1
@@ -19,7 +19,7 @@ jobs:
         runs-on: ubuntu-latest
         steps:
             - name: checkout source
-              uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
+              uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # v4
 
             - name: Run Vale
               uses: errata-ai/vale-action@v2
@@ -35,7 +35,7 @@ jobs:
         runs-on: ubuntu-latest
         steps:
             - name: checkout source
-              uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
+              uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # v4
 
             - name: Build PDF
               uses: xu-cheng/texlive-action/full@v1
@@ -83,7 +83,7 @@ jobs:
         needs: compile-latex
         steps:
             - name: checkout source
-              uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
+              uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # v4
 
             - name: Download artefacts
               uses: actions/download-artifact@v3