chore(deps): update actions/checkout action to v5 (#16031)

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<hr>

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://redirect.github.com/actions/checkout) |
action | major | `v4` -> `v5` |

---

### Release Notes

<details>
<summary>actions/checkout (actions/checkout)</summary>

### [`v5`](https://redirect.github.com/actions/checkout/compare/v4...v5)

[Compare
Source](https://redirect.github.com/actions/checkout/compare/v4...v5)

</details>

---

### Configuration

📅 **Schedule**: Branch creation - "before 5am on the first day of the
month" (UTC), Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
log](https://developer.mend.io/github/rust-lang/cargo).

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Author: ehuss

.github/workflows/audit.yml

@@ -21,7 +21,7 @@ jobs:
           - advisories
           - bans licenses sources
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
     - uses: EmbarkStudios/cargo-deny-action@v2
       # Prevent sudden announcement of a new advisory from failing ci:
       continue-on-error: ${{ matrix.checks == 'advisories' }}

.github/workflows/contrib.yml

@@ -17,7 +17,7 @@ jobs:
       contents: write  # for Git to git push
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
       with:
         fetch-depth: 0
     - name: Install mdbook

.github/workflows/main.yml

@@ -53,7 +53,7 @@ jobs:
   rustfmt:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
     - run: rustup update stable && rustup default stable
     - run: rustup component add rustfmt
     - run: cargo fmt --all --check
@@ -62,30 +62,30 @@ jobs:
   clippy:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - run: rustup update stable && rustup default stable
       - run: rustup component add clippy
       - run: cargo clippy --workspace --all-targets --no-deps -- -D warnings
 
   stale-label:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - run: rustup update stable && rustup default stable
       - run: cargo stale-label
 
   lint-docs:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - run: rustup update stable && rustup default stable
       - run: cargo lint-docs --check
 
   # Ensure Cargo.lock is up-to-date
   lockfile:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - run: rustup update stable && rustup default stable
       - run: cargo update -p cargo --locked
 
@@ -96,7 +96,7 @@ jobs:
       BASE_SHA: ${{ github.event.pull_request.base.sha }}
       HEAD_SHA: ${{ github.event.pull_request.head.sha != '' && github.event.pull_request.head.sha || github.sha  }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
         with:
           fetch-depth: 0
       - run: rustup update stable && rustup default stable
@@ -170,7 +170,7 @@ jobs:
           other: i686-pc-windows-gnu
     name: Tests ${{ matrix.name }}
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
     - name: Dump Environment
       run: ci/dump-environment.sh
     # Some tests require stable. Make sure it is set to the most recent stable
@@ -236,21 +236,21 @@ jobs:
   schema:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
     - run: rustup update stable && rustup default stable
     - run: cargo test -p cargo-util-schemas -F unstable-schema
 
   resolver:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
     - run: rustup update stable && rustup default stable
     - run: cargo test -p resolver-tests
 
   test_gitoxide:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - run: rustup update --no-self-update stable && rustup default stable
       - run: rustup target add i686-unknown-linux-gnu
       - run: rustup target add wasm32-unknown-unknown
@@ -263,7 +263,7 @@ jobs:
   build_std:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
     - run: rustup update nightly && rustup default nightly
     - run: rustup component add rust-src
     - run: cargo build
@@ -273,7 +273,7 @@ jobs:
   docs:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
     - run: rustup update nightly && rustup default nightly
     - run: rustup update stable
     - run: rustup component add rust-docs
@@ -301,6 +301,6 @@ jobs:
   msrv:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
     - uses: taiki-e/install-action@cargo-hack
     - run: cargo hack check --all-targets --rust-version --workspace --ignore-private --locked

.github/workflows/release.yml

@@ -25,7 +25,7 @@ jobs:
 
     steps:
       - name: Checkout the source code
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Publish Cargo to crates.io
         run: ./publish.py