Traceback during docs deploy

[MetRonnie]

The following traceback occurs during the "tidy old versions" step of the deploy workflow. Not preventing the docs from being deployed, but may need investigation

Traceback (most recent call last):
   File "/home/runner/work/cylc-doc/cylc-doc/docs/./bin/version", line 146, in <module>
     main()
   File "/home/runner/work/cylc-doc/cylc-doc/docs/./bin/version", line 142, in main
     args.func(args)
   File "/home/runner/work/cylc-doc/cylc-doc/docs/./bin/version", line 82, in tidy
     release = version._version.release
 AttributeError: 'str' object has no attribute 'release'
 fatal: No pathspec was given. Which files should I remove?

https://github.com/cylc/cylc-doc/actions/runs/4892386529/jobs/8734083505#step:13:14