feat: add all-extras flag to poetry install from file

[shreyashankar]

Describe your changes

• Provide Linear issue reference (e.g. MOD-1234) if available.

I was running into an issue where I wanted to install dependencies via poetry install --all-extras, but the poetry install from file util doesn't support it. My workaround without using the util (below) is kind of clunky:

image=modal.Image.debian_slim().add_local_file("pyproject.toml", "/pyproject.toml", copy=True)
    .pip_install("poetry")
    .run_commands(["poetry config virtualenvs.create false && poetry install --all-extras"])

It's not so bad for me to use my workaround; I just spent quite a bit of time debugging and someone may have a similar issue. Feel free to delete this PR if it's not good to have in the codebase; no worries.

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Check these boxes or delete any item (or this section) if not relevant for this PR.

• Client+Server: this change is compatible with old servers
• Client forward compatibility: this change ensures client can accept data intended for later versions of itself

Note on protobuf: protobuf message changes in one place may have impact to
multiple entities (client, server, worker, database). See points above.

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Changelog

[mwaskom]

Should we also support --extras if we're going to support this one?

[shreyashankar]

I would appreciate it but I am not sure if people commonly use poetry this way!