[1ES] Update core and host pipeline triggers to include 'eng/' path

[liliankasem]

Issue describing the changes in this PR

resolves #issue_for_this_pr

Pull request checklist

• My changes do not require documentation changes
  • Otherwise: Documentation issue linked to PR
• My changes should not be added to the release notes for the next release
  • Otherwise: I've added my notes to release_notes.md
• My changes do not need to be backported to a previous version
  • Otherwise: Backport tracked by issue/PR #issue_or_pr
• I have added all required tests (Unit tests, E2E tests)

Additional information

Update core and host pipeline triggers to include 'eng/' path. All pipelines should have this path to make sure changes to any template does not break other pipelines utilizing that template.