Converge to bazel for running the tests

[zhanyong-wan]

🚀 Feature

Instead of custom test/run_tests.sh scripts, we can standardize the workflow by converging to bazel test (we already use bazel to build/run C++ tests). This will reduce the developer cognitive burden and let us leverage bazel to parallelize tests that can be parallelized (test/run_tests.sh runs the tests sequentially - I imagine at least some of the tests could be run in parallel).