chore(deps): update actions/checkout digest to df4cb1c (#2180)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://redirect.github.com/actions/checkout)
([changelog](https://redirect.github.com/actions/checkout/compare/de0fac2e4500dabe0009e67214ff5f5447ce83dd..df4cb1c069e1874edd31b4311f1884172cec0e10))
| action | digest | `de0fac2` → `df4cb1c` |

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<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0My4yMDkuMCIsInVwZGF0ZWRJblZlciI6IjQzLjIwOS40IiwidGFyZ2V0QnJhbmNoIjoibWFpbiIsImxhYmVscyI6WyJkZXBlbmRlbmNpZXMiXX0=-->

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

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.github/workflows/acceptance-tests.yml

@@ -12,7 +12,7 @@ jobs:
       - name: Check out
         with:
           persist-credentials: false
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
       - uses: jdx/mise-action@1648a7812b9aeae629881980618f079932869151 # v4.0.1
         with:
           version: v2026.5.18

.github/workflows/api-diff.yml

@@ -32,7 +32,7 @@ jobs:
         ${{ contains(github.event.pull_request.labels.*.name, 'breaking-api-change-accepted') }}
 
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
         with:
           persist-credentials: false
       - uses: jdx/mise-action@1648a7812b9aeae629881980618f079932869151 # v4.0.1

.github/workflows/build.yml

@@ -9,7 +9,7 @@ jobs:
   build:
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
         with:
           persist-credentials: false
       - uses: jdx/mise-action@1648a7812b9aeae629881980618f079932869151 # v4.0.1

.github/workflows/codeql.yml

@@ -21,7 +21,7 @@ jobs:
       security-events: write # required for github/codeql-action/analyze to upload SARIF
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
         with:
           persist-credentials: false
 

.github/workflows/generate-api-diff-baseline.yml

@@ -29,7 +29,7 @@ jobs:
     permissions:
       contents: read # checkout + read-only `git fetch origin main` for the verify step
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
         with:
           ref: ${{ github.ref }}
           persist-credentials: false
@@ -90,7 +90,7 @@ jobs:
     permissions:
       contents: write # push regenerated docs/apidiffs back to the renovate branch
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
         with:
           ref: ${{ github.ref }}
           # zizmor: ignore[artipacked] -- needs credentials to push

.github/workflows/generate-protobuf.yml

@@ -14,7 +14,7 @@ jobs:
     permissions:
       contents: read # checkout + read-only `git fetch origin main` for the verify step
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
         with:
           ref: ${{ github.ref }}
           persist-credentials: false
@@ -66,7 +66,7 @@ jobs:
     permissions:
       contents: write # push regenerated sources back to the renovate branch
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
         with:
           ref: ${{ github.ref }}
           # zizmor: ignore[artipacked] -- needs credentials to push

.github/workflows/github-pages.yaml

@@ -32,7 +32,7 @@ jobs:
     if: github.repository == 'prometheus/client_java'
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
         with:
           persist-credentials: false
           fetch-tags: "true"

.github/workflows/jmx-exporter-compatibility.yml

@@ -19,7 +19,7 @@ jobs:
   jmx-exporter-compatibility:
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
         with:
           persist-credentials: false
       - uses: jdx/mise-action@1648a7812b9aeae629881980618f079932869151 # v4.0.1

.github/workflows/multi-version-test.yml

@@ -15,7 +15,7 @@ jobs:
         java: [17, 21, 25]
     steps:
       - name: Check out
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
         with:
           persist-credentials: false
 

.github/workflows/native-tests.yml

@@ -12,7 +12,7 @@ jobs:
       - name: Check out
         with:
           persist-credentials: false
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
       - uses: jdx/mise-action@1648a7812b9aeae629881980618f079932869151 # v4.0.1
         with:
           version: v2026.5.18