Workflow state other run dir fix

[dwsutherland]

workflow-state command and xtrigger no longer works with alternate --run-dir/cylc_run_dir:

This PR fixes this by passing cylc_run_dir through the required machinery.

Check List

• I have read CONTRIBUTING.md and added my name as a Code Contributor.
• Contains logically grouped changes (else tidy your branch by rebase).
• Does not contain off-topic changes (use other PRs for other changes).
• Applied any dependency changes to both setup.cfg (and conda-environment.yml if present).
• Tests are included (or explain why tests are not needed).
• CHANGES.md entry included if this is a change that can affect users
• If this is a bug fix, PR should be raised against the relevant ?.?.x branch.

[hjoliver]

Oops - duplicate?! #6031 (Let's compare our approaches...)