Fix super-linter: add fetch-depth: 0 to checkout to make master branch available

Co-authored-by: electrocucaracha <2782150+electrocucaracha@users.noreply.github.com>
Agent-Logs-Url: https://github.com/electrocucaracha/lint-devstack/sessions/075df27f-8e9d-4ce5-875c-46a7df4da1da

Author: Copilot

.github/workflows/linter.yml

@@ -46,6 +46,7 @@ jobs:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # 6.0.2
         with:
           persist-credentials: false
+          fetch-depth: 0
       - name: Run super-linter validation
         uses: github/super-linter@b807e99ddd37e444d189cfd2c2ca1274d8ae8ef1 # 7
         env: