Update codecov/codecov-action action to v6

Author: renovate[bot]

.github/workflows/rust-instrumented.yml

@@ -63,7 +63,7 @@ jobs:
             --ignore benchmarks/* --ignore 'vortex-test/*' \
             -o ${{ env.GRCOV_OUTPUT_FILE }}
       - name: Codecov
-        uses: codecov/codecov-action@v5
+        uses: codecov/codecov-action@v6
         with:
           name: run-${{ matrix.suite }}
           files: ${{ env.GRCOV_OUTPUT_FILE }}