Bump actions/checkout from 5 to 6 (#66)

Bumps [actions/checkout](https://github.com/actions/checkout) from 5 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v5...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  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/tests.yml

@@ -10,7 +10,7 @@ jobs:
   tests:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: erlef/setup-beam@v1
         with:
           otp-version: "27.x"
@@ -44,7 +44,7 @@ jobs:
         otp: [25.x, 26.x, 27.x]
         elixir: [1.18.x]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: erlef/setup-beam@v1
         with:
           otp-version: ${{matrix.otp}}
@@ -60,7 +60,7 @@ jobs:
         otp: [25.x, 26.x, 27.x]
         elixir: [1.17.x]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: erlef/setup-beam@v1
         with:
           otp-version: ${{matrix.otp}}
@@ -76,7 +76,7 @@ jobs:
         otp: [24.x, 25.x, 26.x]
         elixir: [1.16.x]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: erlef/setup-beam@v1
         with:
           otp-version: ${{matrix.otp}}
@@ -92,7 +92,7 @@ jobs:
         otp: [24.x, 25.x, 26.x]
         elixir: [1.15.x]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: erlef/setup-beam@v1
         with:
           otp-version: ${{matrix.otp}}
@@ -108,7 +108,7 @@ jobs:
         otp: [24.x, 25.x]
         elixir: [1.14.x]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: erlef/setup-beam@v1
         with:
           otp-version: ${{matrix.otp}}