chore(deps): bump actions/checkout from 6 to 7 (#431)

Bumps [actions/checkout](https://github.com/actions/checkout) from 6 to 7.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v6...v7)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -22,7 +22,7 @@ jobs:
     env:
       RUSTFLAGS: -Dwarnings
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@stable
       - name: Cache Cargo dependencies
         uses: actions/cache@v5
@@ -42,7 +42,7 @@ jobs:
     # Same reasoning as Test — z3-sys build exhausts the smithy runner's /tmp.
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@stable
         with:
           components: clippy
@@ -63,7 +63,7 @@ jobs:
     name: Format
     runs-on: [self-hosted, linux, x64, light]
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@stable
         with:
           components: rustfmt
@@ -84,7 +84,7 @@ jobs:
     name: Version Pin Sweep
     runs-on: [self-hosted, linux, x64, light]
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       # Issue #145: fail at PR time if [workspace.package].version drifts from
       # any intra-workspace path-dep `version =` pin or MODULE.bazel — the
       # v0.7.0-class desync that breaks release.yml + publish at tag-push time.
@@ -98,7 +98,7 @@ jobs:
     # the smithy toolchains role.
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@stable
       - name: Cache Cargo dependencies
         uses: actions/cache@v5
@@ -122,7 +122,7 @@ jobs:
     needs: [test]
     runs-on: [self-hosted, linux, x64, rust-cpu]
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@nightly
       - name: Cache Cargo dependencies
         uses: actions/cache@v5
@@ -158,7 +158,7 @@ jobs:
     # table). Move once smithy ships kani-verifier + CBMC.
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - name: Install Kani
         run: cargo install --locked kani-verifier && cargo kani setup
       - name: Run Kani proofs
@@ -169,7 +169,7 @@ jobs:
     name: Rivet Validation
     runs-on: [self-hosted, linux, x64, rust-cpu]
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@stable
       - name: Cache Cargo dependencies
         uses: actions/cache@v5
@@ -210,7 +210,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 45
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - name: Install Nix
         uses: cachix/install-nix-action@v31
         with:
@@ -239,7 +239,7 @@ jobs:
     # `cargo test --workspace` gate is NOT taxed with a C-library build graph.
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@stable
       - name: Cache Cargo dependencies
         uses: actions/cache@v5

.github/workflows/compliance.yml

@@ -37,7 +37,7 @@ jobs:
           case "$TAG" in v*) ;; *) echo "::error::tag '$TAG' must start with v"; exit 1 ;; esac
           echo "tag=$TAG" >> "$GITHUB_OUTPUT"
 
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
         with:
           ref: ${{ steps.tag.outputs.tag }}
 

.github/workflows/fuzz-smoke.yml

@@ -74,7 +74,7 @@ jobs:
     # safe to interpolate.
     continue-on-error: ${{ matrix.gating == false }}
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Install nightly Rust
         uses: dtolnay/rust-toolchain@nightly

.github/workflows/publish-to-crates-io.yml

@@ -44,7 +44,7 @@ jobs:
     permissions:
       contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
         with:
           ref: ${{ inputs.tag || github.ref }}
 

.github/workflows/release.yml

@@ -61,7 +61,7 @@ jobs:
             os: macos-latest
             archive: tar.gz
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
         with:
           ref: ${{ inputs.tag || github.ref }}
 
@@ -127,7 +127,7 @@ jobs:
       id-token: write
       attestations: write
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
         with:
           ref: ${{ inputs.tag || github.ref }}
 

.github/workflows/signing-e2e.yml

@@ -90,7 +90,7 @@ jobs:
       contents: read
       id-token: write
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - uses: dtolnay/rust-toolchain@stable