Update actions/checkout digest to c2d88d3

Author: renovate[bot]

.github/workflows/rust.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
     # actions/checkout@v2
-    - uses: actions/checkout@ff7abcd0c3c05ccf6adc123a8cd1fd4fb30fb493
+    - uses: actions/checkout@c2d88d3ecc89a9ef08eebf45d9637801dcee7eb5
     - name: Report cargo version
       run: cargo --version
     - name: Report rustfmt version
@@ -26,7 +26,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
     # actions/checkout@v2
-    - uses: actions/checkout@ff7abcd0c3c05ccf6adc123a8cd1fd4fb30fb493
+    - uses: actions/checkout@c2d88d3ecc89a9ef08eebf45d9637801dcee7eb5
     - name: Report cargo version
       run: cargo --version
     - name: Report Clippy version
@@ -46,7 +46,7 @@ jobs:
         os: [ ubuntu-24.04, windows-2022, macos-14 ]
     steps:
     # actions/checkout@v2
-    - uses: actions/checkout@ff7abcd0c3c05ccf6adc123a8cd1fd4fb30fb493
+    - uses: actions/checkout@c2d88d3ecc89a9ef08eebf45d9637801dcee7eb5
     - uses: actions-rs/toolchain@88dc2356392166efad76775c878094f4e83ff746
       with:
         profile: minimal