add pakcage without peotry config [tool.poetry.build] script would raise keyError

[zsluedem]

• I have searched the issue tracker and believe that this is not a duplicate.

Make sure you run commands with -v flag before pasting the output.

Steps to reproduce

pdm add starknet-py

Actual behavior

Adding group default to lockfile
Adding packages to default dependencies: starknet-py
STATUS: Resolving dependencies
pdm.termui: ======== Start resolving requirements ========
pdm.termui:   starknet-py
pdm.termui:   python>=3.10
pdm.termui:   Adding requirement starknet-py
pdm.termui:   Adding requirement python>=3.10
pdm.termui: ======== Starting round 0 ========
unearth.preparer: Using cached <Link https://files.pythonhosted.org/packages/cb/98/9c5b8a9ea84614d8d2c26ba815d955f207e8b60a4e15f128c634ef3d5ec7/starknet_py-0.15.2.tar.gz (from https://pypi.org/simple/starknet-py/)>
Traceback (most recent call last):
  File "/home/will/.local/bin/pdm", line 8, in <module>
    sys.exit(main())
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/core.py", line 268, in main
    return Core().main(args)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/core.py", line 192, in main
    raise cast(Exception, err).with_traceback(traceback) from None
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/core.py", line 187, in main
    self.handle(project, options)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/core.py", line 153, in handle
    command.handle(project, options)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/cli/commands/add.py", line 60, in handle
    actions.do_add(
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/cli/actions.py", line 285, in do_add
    resolved = do_lock(
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/cli/actions.py", line 104, in do_lock
    mapping, dependencies = resolve(
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/resolver/core.py", line 35, in resolve
    result = resolver.resolve(requirements, max_rounds)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/resolvelib/resolvers.py", line 546, in resolve
    state = resolution.resolve(requirements, max_rounds=max_rounds)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/resolvelib/resolvers.py", line 426, in resolve
    name = min(unsatisfied_names, key=self._get_preference)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/resolvelib/resolvers.py", line 203, in _get_preference
    return self._p.get_preference(
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/resolver/providers.py", line 85, in get_preference
    is_backtrack_cause = any(dep.identify() in backtrack_identifiers for dep in self.get_dependencies(candidate))
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/resolver/providers.py", line 182, in get_dependencies
    deps, requires_python, _ = self.repository.get_dependencies(candidate)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/models/repositories.py", line 82, in get_dependencies
    requirements, requires_python, summary = getter(candidate)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/models/repositories.py", line 41, in wrapper
    result = func(self, candidate)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/models/repositories.py", line 213, in _get_dependencies_from_metadata
    deps = prepared.get_dependencies_from_metadata()
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/models/candidates.py", line 510, in get_dependencies_from_metadata
    self.req.project_name, self.metadata.requires or [], extras  # type: ignore[arg-type]
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/models/candidates.py", line 496, in metadata
    result = self.prepare_metadata()
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/models/candidates.py", line 436, in prepare_metadata
    pyproject = PyProject(pyproject_toml, ui=self.environment.project.core.ui)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/project/toml_file.py", line 18, in __init__
    self._data = self.read()
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/project/project_file.py", line 32, in read
    metadata, settings = converter.convert(None, self._path, None)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/formats/poetry.py", line 199, in convert
    return converter.convert()
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/formats/base.py", line 55, in convert
    self._data[key] = func(self, value)
  File "/home/will/.local/share/pdm/venv/lib/python3.10/site-packages/pdm/formats/poetry.py", line 175, in build
    value = value["script"]
KeyError: 'script'

Expected behavior

Denpendency starknet-py should be added normally.

Environment Information

# Paste the output of `pdm info && pdm info --env` below:
PDM version:
  2.6.1
Python Interpreter:
  /chain/zk/test/.venv/bin/python (3.10)
Project Root:
  /chain/zk/test
Local Packages:
  
{
  "implementation_name": "cpython",
  "implementation_version": "3.10.10",
  "os_name": "posix",
  "platform_machine": "x86_64",
  "platform_release": "5.15.0-72-generic",
  "platform_system": "Linux",
  "platform_version": "#79-Ubuntu SMP Wed Apr 19 08:22:18 UTC 2023",
  "python_full_version": "3.10.10",
  "platform_python_implementation": "CPython",
  "python_version": "3.10",
  "sys_platform": "linux"
}

[zsluedem]

The the pyproject.toml in starknet-py .

[tool.poetry.build]
generate-setup-file = true

doesn't contains script value. I am not sure whether this should be a bug in pdm or a bug in starknet-py