chore(deps): update actions/checkout digest to c2d88d3 (#2880)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| actions/checkout | action | digest | `71cf226` -> `c2d88d3` |

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.github/workflows/checks.yml

@@ -21,7 +21,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@71cf2267d89c5cb81562390fa70a37fa40b1305e
+    - uses: actions/checkout@c2d88d3ecc89a9ef08eebf45d9637801dcee7eb5
     - name: Install nightly@nightly toolchain
       uses: actions-rust-lang/setup-rust-toolchain@1780873c7b576612439a134613cc4cc74ce5538c # v1.15.2
       with:
@@ -35,7 +35,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@71cf2267d89c5cb81562390fa70a37fa40b1305e
+    - uses: actions/checkout@c2d88d3ecc89a9ef08eebf45d9637801dcee7eb5
     - name: Install stable@stable toolchain
       uses: actions-rust-lang/setup-rust-toolchain@1780873c7b576612439a134613cc4cc74ce5538c # v1.15.2
       with: