Error with non-ascii characters in pyproject.toml

[abersheeran]

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

Failed to build package, try parsing project files.
Error occurs
Traceback (most recent call last):
  File "c:\users\aber\.local\pipx\venvs\pdm\lib\site-packages\pdm\models\builders.py", line 146, in __init__
    spec = toml.load(f)
  File "c:\users\aber\.local\pipx\venvs\pdm\lib\site-packages\toml\decoder.py", line 156, in load
    return loads(f.read(), _dict, decoder)
UnicodeDecodeError: 'gbk' codec can't decode byte 0xac in position 181: illegal multibyte sequence

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "c:\users\aber\.local\pipx\venvs\pdm\lib\site-packages\pdm\iostream.py", line 140, in logging
    yield logger
  File "c:\users\aber\.local\pipx\venvs\pdm\lib\site-packages\pdm\installers\synchronizers.py", line 336, in synchronize
    handlers[install_self[0]](install_self[1])
  File "c:\users\aber\.local\pipx\venvs\pdm\lib\site-packages\pdm\installers\synchronizers.py", line 146, in install_candidate
    installer.install(can)
  File "c:\users\aber\.local\pipx\venvs\pdm\lib\site-packages\pdm\installers\installers.py", line 46, in install
    self.install_editable(candidate.ireq)
  File "c:\users\aber\.local\pipx\venvs\pdm\lib\site-packages\pdm\installers\installers.py", line 71, in install_editable
    with EnvBuilder(ireq.unpacked_source_directory, self.environment) as builder:
  File "c:\users\aber\.local\pipx\venvs\pdm\lib\site-packages\pdm\models\builders.py", line 150, in __init__
    raise BuildError(e) from e
pdm.exceptions.BuildError: 'gbk' codec can't decode byte 0xac in position 181: illegal multibyte sequence

Steps to reproduce

Write any non-ASCII characters in the pyproject.toml.

Environment Information

# Paste the output of `pdm info && pdm info --env` below:
PDM version:        1.4.2
Python Interpreter: C:/Users/Aber/AppData/Local/Programs/Python/Python39/python.exe (3.9.2)
Project Root:       C:/Users/Aber/Documents/xxx
{
  "implementation_name": "cpython",
  "implementation_version": "3.9.2",
  "os_name": "nt",
  "platform_machine": "AMD64",
  "platform_release": "10",
  "platform_system": "Windows",
  "platform_version": "10.0.19041",
  "python_full_version": "3.9.2",
  "platform_python_implementaiton": "CPython",
  "python_version": "3.9",
  "sys_platform": "win32"
}