[core][ci] Run dag microbenchmark seperately

[rickyyx]

Why are these changes needed?

Related issue number

Checks

• I've signed off every commit(by using the -s flag, i.e., git commit -s) in this PR.
• I've run scripts/format.sh to lint the changes in this PR.
• I've included any doc changes needed for https://docs.ray.io/en/master/.
  • I've added any new APIs to the API Reference. For example, if I added a
    method in Tune, I've added it in doc/source/tune/api/ under the
    corresponding .rst file.
• I've made sure the tests are passing. Note that there might be a few flaky tests, see the recent failures at https://flakey-tests.ray.io/
• Testing Strategy
  • Unit tests
  • Release tests
  • This PR is not tested :(

[rkooo567]

TESTS_TO_RUN='pattern'

is there a way to just utilize this? If this pattern is regex, we can just use it?

[rickyyx]

TESTS_TO_RUN='pattern'

is there a way to just utilize this? If this pattern is regex, we can just use it?

it's not a regex pattern yet, but maybe making that a regex pattern is a better idea.

[rickyyx]

https://buildkite.com/ray-project/release/builds/5854#018cff09-7ad7-4987-a4c9-5c7ef18040d1 test ok