Give artifacts unique names rather than over-write them

Author: steve-sullivan

.github/workflows/build.yml

@@ -30,6 +30,5 @@ jobs:
         if: ${{ always() }}
         uses: actions/upload-artifact@v4
         with:
-          name: artifacts
+          name: artifacts-${{ matrix.os }}-${{ matrix.ruby }}
           path: artifacts/**
-          overwrite: true