chore(ci): remove llvm cov (#14565)

Co-authored-by: xxchan <[email protected]>

ci/scripts/run-unit-test.sh

@@ -10,10 +10,6 @@ cd ${REPO_ROOT}/src/expr/udf/python
 python3 -m pytest
 cd ${REPO_ROOT}
 
-echo "+++ Run unit tests with coverage"
+echo "+++ Run unit tests"
 # use tee to disable progress bar
-NEXTEST_PROFILE=ci cargo llvm-cov nextest --lcov --output-path lcov.info --features failpoints,sync_point --workspace --exclude risingwave_simulation
-
-echo "--- Codecov upload coverage reports"
-curl -Os https://uploader.codecov.io/latest/linux/codecov && chmod +x codecov
-./codecov -t "$CODECOV_TOKEN" -s . -F rust
+NEXTEST_PROFILE=ci cargo nextest run --features failpoints,sync_point --workspace --exclude risingwave_simulation