Bump actions/checkout from 6 to 7

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>

Author: dependabot[bot]

.github/workflows/main.yml

@@ -21,7 +21,7 @@ jobs:
 
     steps:
       - name: Checkout tree
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
 
       - name: Set-up OCaml
         uses: ocaml/setup-ocaml@v3
@@ -38,7 +38,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout tree
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
       - name: Set-up OCaml
         uses: ocaml/setup-ocaml@v3
         with:
@@ -49,7 +49,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout tree
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
       - name: Set-up OCaml
         uses: ocaml/setup-ocaml@v3
         with:
@@ -60,7 +60,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout tree
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
       - name: Set-up OCaml
         uses: ocaml/setup-ocaml@v3
         with:

.github/workflows/pre-commit.yml

@@ -16,7 +16,7 @@ jobs:
     steps:
       # Get the code
       - name: Checkout
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
 
       # Set up Python with built-in pip caching
       - name: Set up Python