Install Poetry using locked dependencies

[bkeryan]

Problem to Solve

Installing Poetry with unlocked dependencies sometimes breaks due to regressions in dependencies.

Proposed Solution

Use a traditional pip-compile workflow to create a locked requirements.txt.

If inputs.poetry-version matches the default, use the lock file. Otherwise, use unlocked dependencies. I don't want to maintain multiple lock files for different versions of Poetry.

Use Renovate to keep the lock file up to date.

@mshafer-NI previously suggested using poetry export but I think that exports the dependencies for the current project, not for Poetry itself.

AB#3233815