Fixed version restore behaviour when executing 'poetry run' commands on Linux with poetry >= 1.0.0b2

[lmoretto]

Hello,
as of version 1.0.0b2, on Linux, the poetry run command uses os.execvp function instead of spawning a new subprocess.

For poetry-dynamic-versioning this change has the side-effect that the atexit hook is no longer called and, as a consequence, the original version string in pyproject.toml is not properly restored.

The proposed solution is to also patch poetry.console.command.run.RunCommand.handle function in order to immediately call deactivate before executing the desired command/script.

[mtkennerly]

Thanks for this! Just one minor change I'd like to see before merging.

[mtkennerly]

@lmoretto This is now available in 0.3.2.

[lmoretto]

Nice, thank you!