Support --all-extras flag in poetry export

[cpcloud]

• I have searched the issues of this repo and believe that this is not a duplicate.
• I have searched the FAQ and general documentation and believe that my question is not already covered.

Feature Request

I find the --all-extras flag of poetry install to be very useful. It would be even more useful if the flag was available for poetry export as well!

[dimbleby]

You want https://github.com/python-poetry/poetry-plugin-export, not this repository

I expect a merge request implementing this would likely be accepted, I guess you should be able to copy the mechanism from poetry install

[johnthagen]

Related/duplicate of:

• (🎁) poetry export should have an --all option #45

[cpcloud]

Ah, great. I'll close this issue then.