Potential fix for code scanning alert no. 13: Workflow does not contain permissions

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

Author: CypherPotato

.github/workflows/dotnet-tests.yml

@@ -2,6 +2,8 @@
 # For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-net
 
 name: Run tests
+permissions:
+  contents: read
 
 on:
   push: