Adds link to "Dependency specification" in the `pyproject.toml` reference

* fix(flake8): drop F401 from __init__.py ignores

* Update .flake8

The URL path is used by `mock_download` to determine the path relative
to the fixtures directory to get the download result.

I believe this has been passing on CI because the `copy_or_symlink` call
in `mock_download` happily creates a symlink to a non-existent path, but
when running on Windows without permission to create symlinks,
`shutil.copyfile` is called as a fallback, and fails trying to copy a
non-existent file.

Co-authored-by: Bjorn Neergaard <bjorn@neersighted.com>

* doc(cli): move `Options` headers one level down for `self`

* doc(cli): remove backticks in headers for consistency

According to
https://github.com/python-poetry/poetry/issues/4864#issuecomment-1002465303:
> The `--dev-only` option was never available in a release, but was already
> available in the master branch. Because it's a feature we will probably not
> backport this to the 1.1 branch.

Given that the option was only ever present when installing Poetry from master
and was never available as part of a release, I think it's clearer to just
remove all references to it rather than include a deprecation notice that would
only be relevant to a tiny fraction of Poetry users.

* Exclude .venv from Time Machine backups

* Remove leftover print statements

* Make backup exclusion test only run on darwin

* Add comment explaining backup exclusion xattr value

* Use plistlib to generate backup exclusion xattr value

* Only install xattr on darwin

* Add TODO comment

* Merge fix

* Only import xattr on macOS test

* Try fixing CI error

* Add type annotations

* Fix CI errors

* Add spacing pyproject.toml

Co-authored-by: Bjorn Neergaard <bjorn@neersighted.com>

* Move mypy ignore to `pyproject.toml`

Co-authored-by: Bjorn Neergaard <bjorn@neersighted.com>

* Add Failing test for #5727

* Fixes #5727

Co-authored-by: Dos Moonen <d.moonen@nki.nl>

We updated our version of importlib_metadata, so we might as well take
advantage of it to have full compatibility with the features introduced
in Python 3.10.

* Fix running scripts of editable deps on Windows
* Add Windows-specific logic to fix existing test

Co-authored-by: Kevin Conley <kevincon@users.noreply.github.com>

Co-authored-by: Bjorn Neergaard <bjorn@neersighted.com>

Co-authored-by: Bjorn Neergaard <bjorn@neersighted.com>

also support symlinked temp directories

use `3.11-dev` instead of pinning a beta

Co-authored-by: Bjorn Neergaard <bjorn@neersighted.com>

This change is intended to help migrate validation of sections in
pyproject.toml that are not relevant to poetry-core into poetry. This
allows for poetry frontend specific configuration to be introduced
without dependent changes in poetry-core.