add missing <memory> include

[acxz]

Why are these changes needed?

Fixes build issue.

Related issue number

Closes #19082

Checks

• 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 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 :(

[jjyao]

Sees clang-format failed: https://buildkite.com/ray-project/ray-builders-pr/builds/15222#1595ea57-70ad-4258-872d-1479db28a4a8. You can follow the instruction here: https://docs.ray.io/en/master/getting-involved.html#lint-and-formatting.

[acxz]

Added a linting commit.