Bump actions/checkout from 2 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 2 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v2...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>

Author: dependabot[bot]

.github/workflows/miss_hit.yml

@@ -14,7 +14,7 @@ jobs:
 
     steps:
 
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v6
       with:
         submodules: true
         fetch-depth: 1

.github/workflows/update_submodules.yml

@@ -63,7 +63,7 @@ jobs:
     steps:
 
       - name: Clone repo
-        uses: actions/checkout@v3
+        uses: actions/checkout@v6
         with:
           submodules: true